For most of the 2010s, digital advertising had a trust problem. Five years ago, adtech was moving from instability toward accountability. However, lately that velocity has reversed — and the system is drifting back toward the unstable state it came from.
To the astute observer, in the last five years, there was perceptible movement toward martech that was more transparent and accountable. That was true until a reversal started to assert itself in 2025 and in 2026. Market forces seem to be working against the progress that had been made toward a more trusted system so that now it seems as though martech is going in reverse – relearning its chaotic old habits.
We know that for most of the 2010s, digital advertising had a trust problem. The Facebook data crises, the rise of ad fraud, and the “brand safety” scandals gave marketing tech a black eye. It was universally acknowledged that the industry had to clean up its act.
Then, starting in about 2020, we see a redemption arc. Consent frameworks got built. The IAB, the ANA, and the Media Rating Council pushed for standardized, log-level transparency. Advertisers were told, credibly, that the system was moving toward equilibrium — becoming more stable and more accountable every year.
Sadly, the nascent movement toward trusted and transparent marketing tech has reversed in the last 12 months.
The five of the industry’s foundational fixes that showed such promise – traffic verification, privacy, algorithmic transparency, market structure, and TV measurement – have each seen their velocity flip – like Venus going in retrograde.
What was heading toward a stable state is now heading back toward an unstable one: the same opacity, concentration, and unaccountability marketers thought they’d left behind.
Here are the market forces that are sabotaging the industry movement toward a trust web.
1. Traffic Verification: Phase Change — From Independent to Entangled
Independent ad verification exists to answer one question objectively: was this ad actually seen by a real person in a safe environment? That independence just got a lot murkier. In August 2026, Nielsen — already the dominant name in audience measurement — agreed to acquire DoubleVerify, one of the two major independent verification vendors, in an all-cash deal valued at approximately $2.15 billion, with DoubleVerify shareholders receiving $13.60 per share.
The combined company is expected to generate over $4 billion in pro-forma revenue and extend Nielsen’s reach across a media ecosystem that touches more than $300 billion in advertising spend. Nielsen and DoubleVerify have both framed the deal as strengthening “independence and trust,” but the practical effect is that the company grading the quality of media buys (verification) and the company measuring the audience for those same buys (ratings) are becoming one company. Trade press covering the deal noted plainly that it “raises questions about maintaining its independent verification role,” (1).
This is not a one-off. It’s the latest step in a broader pattern of consolidation among the vendors advertisers rely on to check the platforms’ own numbers — and every consolidation step removes one more party with an incentive to disagree with the seller.
2. Privacy: Reverting to an Earlier, Less Stable Time
Ask most marketers whether it’s legal to email someone who has never given a company their email address, and many assume the answer is no. It isn’t. Under the U.S. CAN-SPAM Act, a business can legally send an initial, unsolicited commercial email to anyone — no opt-in, no prior relationship, no consent of any kind required — as long as the message includes accurate sender information and a functioning opt-out mechanism. The FTC’s own compliance guide is explicit that the law “does not require that you get permission before you can send someone a commercial email.”
In practice, this means that simply visiting a website — where a tracking pixel, a form abandonment, or a third-party data broker captures an email address — can be a sufficient trigger for a company to start emailing you commercial messages indefinitely, with the burden placed entirely on the recipient to opt out. Compare that to the EU’s ePrivacy Directive and GDPR, or Canada’s CASL, both of which require affirmative opt-in consent before the first message is ever sent. The U.S. remains one of the only major markets built on an opt-out model rather than an opt-in one. (2)
The result is a widening gap between what consumers assume the law protects and what it actually permits. We see a growing list of companies who empower this level of digital “stalking” – all specifically built to convert anonymous site visits into outbound email and retargeting lists.
3. AI Algorithms: Optimization You’re Told to Trust, Not Verify
As Google’s Performance Max and Meta’s Advantage+ have become the default way to buy on both platforms, advertisers have lost visibility into decisions that used to be theirs to make: which audience segment, which placement, which creative variant is actually driving a result. Industry coverage of both systems consistently uses the same word — “black box” — to describe how they operate, noting that both ecosystems became more automated and more opaque through 2025 and into 2026.
It is no coincidence that both Google’s and Meta’s revenue soared (Google ad revenue reached $82.3 billion in a single quarter and Meta’s automated ad products running at a $60 billion annual pace) just as the black box got blacker and bigger.
Google has responded to years of advertiser frustration with incremental transparency features — asset-level disapprovals, better demographic reporting — but analysts covering the update were candid that it also confirms “advertisers have been frustrated with the black-box nature of PMax for years.” On the Meta side, Advantage+ campaigns pool prospecting and retargeting spend together by default, making it structurally difficult for advertisers to tell whether the algorithm is generating new demand or simply taking credit for purchases that would have happened anyway — a problem practitioners say now requires manual incrementality testing to even detect.
None of the major platforms publish the underlying weighting of their bidding or ranking models. Advertisers are asked to feed the machine creative and budget and simply trust the output — a level of blind faith that would have been unacceptable in the log-level-transparency era of 2018–2020.
The “Trust the AI” is a definite step backwards just as we were emerging from the fog of programmatic’s faux promises of “right person, right time, right message.”
Dang it.
4. Consolidation: Past the Tipping Point
Efforts to diversify media buying — retail media networks, TikTok, the open web, CTV apps — have not slowed the concentration of ad dollars in Google, Meta, and Amazon. If anything, the “triopoly” has tightened its grip over the last five years, both across total U.S. advertising and within digital specifically (3).
| Metric | 2020/2021 | 2023 | 2025 | 2026 (est.) |
| Google + Meta + Amazon share of ALL U.S. ad spending (digital + traditional) | 47.1% | ~53% | 58.8% | — |
| Google + Meta + Amazon share of U.S. DIGITAL ad spending | 64.0% | ~68% | ~72% | — |
| Google + Meta + Amazon share of WORLDWIDE digital ad spending | — | — | ~60% | 62.3% |
| Amazon’s individual share of worldwide digital ad spend | — | — | 8.0% (2024) | 9.0% |
The through-line: the triopoly’s share of total U.S. advertising — including TV, radio, and print — grew from 47.1% in 2020 to 58.8% in 2025. Within digital specifically, the three companies controlled 64.0% of U.S. digital spend in 2021 and roughly 72% by 2025.
The reason for this consolidation is covered glowingly by industry pundits by describing the trend as “the compounding advantage of first-party data, AI integrations, and audience reach” that smaller platforms and traditional media simply cannot replicate.
Seriously? Claiming that these platforms have better targeting data belies the issue that too much of their targeting data is wrong, inaccurate or false.
According to NC University, the estimate is that approximately 33% of the target profile data is inaccurate. While Meta’s inaccuracy leans toward incorrectly inferred interests, Google’s profiling errors lean heavily toward misclassified demographics and “outside-of-target” delivery. Let’s put some dollars behind these stats. In essence, the targeting promises of Meta and Google mean that, in reality, $1 out of $3 is wasted before a single ad has run (4).
Clearly, something else is going on. The walled gardens dominate because this consolidation made buying media easier for agencies than the open web. This helped agencies increase their profits and reduce media buying hassles. No wonder agencies like it better because it is so much easier to work with just a few platforms even if the better targeting data premise is a myth. Afterall, there is no way to verify the targeting of these platforms.
Brutal truth is that while fragmentation of ad supply has increased; concentration of ad dollars has increased faster. The real losers are, again, advertisers.
5. CTV: Programmatic’s Original Sins, Now Streaming in 4K
Connected TV was supposed to be the fix — measurable, addressable, accountable television advertising. Instead, industry benchmarks describe it as inheriting the exact problems that took a decade to partially clean up on the open web. The ANA’s own CEO described the space bluntly in 2025: marketers are “managing through fragmented and opaque programmatic supply chains,” a description he applied specifically as CTV’s share of programmatic spend which surged past 40% of the total.
Independent research found that as much as one in four CTV dollars is wasteful or unproductive, with no more than roughly a third of ad dollars in some channels reaching the intended audience. CTV carries an extra layer of uncertainty because it often relies on IP-address-based household matching rather than verified individual identity, a methodology independent testing has found to be materially inaccurate against real subscriber and set-top data. The ANA has made real progress narrowing waste in the standard open-web supply chain over the past two years, for example by clamping down on MFA sites (made-for-advertising). However, that progress has been offset by CTV inventory that is increasingly becoming the hardest media channel to independently verify.
It’s fair to say that, at the current course and speed, CTV is lining up to be “Programmatic v2.”
The infrastructure between programmatic and CTV is the same; opaque chain of exchanges, resellers, and inventory arbitrage that plagues the supply chain. Again, as in programmatic media, CTV inventory is similarly wrapped up in premium-sounding formats that are priced accordingly even though reach numbers remain genuinely difficult for any advertiser to independently confirm (5).
Conclusion: Advertisers Are Paying for the U-Turn
Put the five trends together and a pattern emerges: the entities meant to ensure transparency – independent verification, privacy law, algorithmic disclosure, competitive market structure, and TV measurement standards — are all trending toward less transparency, not more.
Nielsen buying its own watchdog.
A privacy law that still permits emailing strangers who never opted in.
Two dominant ad platforms whose optimization logic is proprietary by design.
And a CTV market repeating programmatic’s early, unaccountable years at premium prices.
Advertisers are the ones absorbing the cost of this reversal. They pay verification vendors whose independence is shrinking. They inherit legal and reputational risk from an email ecosystem built on assumed rather than actual consent. They fund algorithmic “optimization” they cannot audit, on platforms that keep taking a larger share of every incremental ad dollar. They are increasingly in a CTV supply chain nobody can fully see through.
Consumers also pay a steep price in this reversal of transparency fortunes. Consumers have less media choices, fewer protections and more SPAM than ever.
Why did this reversal happen? The simple answer is market forces. Adtech had maxed out in terms of growth potential which explains why adtech ventures are persona non grata in VC circles. So, when a “mature” market stagnates – growth happens from consolidation, retrenchment, and bottom-line revenue growth – however it can get there.
This reversal is the consequence of what happens when scale, automation, and consolidation converge and move faster than the accountability mechanisms meant to keep pace with them.
For now, marketers should assume they are buying media with less visibility than they had five years ago, not more. They should be wary again of targeting nirvana promises and impression reach. Mostly, though, they need to realize the progress made in creating a better martech ecosystem has hit a speed bump.
Advertisers – plan accordingly. (Yes – this is a bummer.)
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Sources:
(1) Nielsen Holdings press release, Aug. 6, 2026; DoubleVerify SEC Form 8-K, Aug. 2026; Forbes, “Nielsen To Buy DoubleVerify For $2.15 Billion In Ad Measurement Deal,” Aug. 8, 2026; Deadline, Aug. 6, 2026.)
(2) Federal Trade Commission, “CAN-SPAM Act: A Compliance Guide for Business”; CookieYes, “CAN-SPAM Act: Compliance Guide for Businesses,” 2025; TermsFeed, “Legal Requirements for Email Marketing,” 2026; Securiti, “CAN-SPAM Email Compliance,” 2024.
(3) eMarketer/Insider Intelligence, “These three companies will pocket 64.0% of all US digital ad spending in 2021”; eMarketer, “As the duopoly stagnates, Amazon is hot on Meta’s tail,” US Ad Spending 2023; PPC Land, “Digital advertising triopoly gains overall market share while facing competition,” citing EMARKETER, July 29, 2025; eMarketer, “Meta to Surpass Google in Digital Ad Revenues for First Time Ever,” Apr. 2026; eMarketer/Insider Intelligence, “These three companies will pocket 64.0% of all US digital ad spending in 2021”; AdExchanger, “More Performance, Less Transparency: Inside Meta’s Advantage+ Shopping Black Box”; Pixis, “Advantage+ vs. Performance Max Head-to-Head (2026)”; BuildMVPFast, “AI Ad Targeting: Advantage+ vs Performance Max Compared,” 2026.
(4) NC University https://news.ncsu.edu/2022/03/new-study-reveals-why-facebook-ads-can-miss-target/; https://newage.agency/en/blog/google-s-targeting-accuracy-issues/
(5) ANA (Association of National Advertisers), Programmatic Transparency Benchmark releases, Q2–Q4 2025; ANA press release, Aug. 14, 2025 (Bob Liodice quote); Taqtics, “The Number CTV Platforms Won’t Show You,” citing CIMM/Go Addressable/Truthset match-accuracy testing (Nov. 2025); ANA Programmatic Media Supply Chain Transparency Study; AI Digital, “CTV Media Buying: How Connected TV Ads Work,” 2026.
