Haha, no. You're falling for the trick, or maybe you're just 10 years behind.
Publishers (and retailers, and anyone with a dataset) seek out adtech partner companies, to justify high CPMs and to sell their audience data. Adtech companies are market-makers, it's been years since the data they can get independently of supply-side partners was worth shit.
The publisher is the one with the cookie warning and consent forms! The publisher is the one who wants you to log in with a stable ID! The publisher is the one with a model of you regardless of your ad or tracker blocker settings! The adtech companies will sell you downstream for sure, but the publishers are the ones deploying as many tricks as possible to gather data.
And yeah, adtech companies will advise them about how to effectively gather data. That's a lot less about "tricks" and more about how to build salable taxonomies instead of data lakes full of garbage. To the extent it's about tricks, it's more often the adtech companies having to patiently but firmly explain, no, you can't just hardcode a single consent state for all visitors and send that to us in lieu of a real CMP. (A purely theoretical example, of course...)