Cannes Lions is usually where the ad industry congratulates itself. This year it doubled as a mid-year reckoning, and for publishers the two questions on everyone’s lips cut right to the business model: Who is going to pay for the open web in an AI world? And: is agentic media buying a genuine fix — or just a freshly branded ad-tech tax? Layered on top was a third, aimed at the middle of the value chain: does anyone still need the traditional agency?
01The open web’s funding crisis, said out loud
The first question is existential and it’s no longer hypothetical. With AI search siphoning traffic (zero-click is now the majority of queries) and budgets consolidating into retail-media and platform walled gardens, the revenue that historically funded independent journalism and the open web is shrinking from multiple directions at once. Cannes conversations reportedly treated this as a checkpoint, not an abstraction: the people who buy and sell advertising are openly asking who underwrites the open web when search refers less traffic and the giants keep more spend inside their gardens.
02“Agentic” — fix or tax?
The second question is the skeptical counterweight to all the agentic hype. AI agents promise efficiency: autonomous buying, optimization, less manual work. But the industry has seen this movie. Every previous “efficiency” layer — from ad networks to the programmatic supply chain — also extracted its own margin, the so-called ad-tech tax. The fear voiced at Cannes is that agentic buying could become another intermediary layer skimming a cut while presenting itself as savings. And the agency question is part of the same theme: some brands are openly questioning agencies of record — one CMO reportedly hasn’t used a creative agency in years — as AI tools let advertisers do more in-house.
Cannes 2026 traded some of the champagne for hard questions, and that's healthy for publishers.
03Why marketers should care
| "Is agentic buying a new ad tax?" is a question about your money | Every layer between budget and impression takes something. The industry asking this out loud is the opening to ask it of your own supply chain, with specifics, and get an answer. |
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| Disintermediation is running in both directions | Brands are questioning agencies, agencies are questioning intermediaries, and agents are automating what used to be a negotiation. Every link is being re-examined, including the ones you pay for. |
| "Who pays for the open web" reaches your media plan eventually | If the answer settles badly, the environments your brand appears in get thinner. It is a supply-quality question dressed as an industry debate. |
04What marketers should do
05The bottom line
Cannes 2026 traded some of the champagne for hard questions, and that’s healthy for publishers. The funding of the open web is now an out-loud industry concern, the agentic-buying boom is getting the skeptical scrutiny it deserves, and the whole value chain — agencies included — is being re-examined for what it actually adds. Publishers should treat this as an invitation: make the case for your value, insist that new layers justify their cut, and double down on the audience and trust that no agent can automate away.