If google.com isn’t using any privileged position (I was guessing they were, from your comment), then where’s the problem? There’s no antitrust: third-party cookies are a privacy problem, and the browser industry has unanimously decided to remove them, and in fact everyone else has already removed them—Google is last here. The fact that one of the browser providers (and yes, maker of the biggest one) happens to be an advertising company should then be irrelevant—either Google is simply doing things better than everyone else in the advertising industry, or they’re behaving anticompetitively in some other way. But I don’t see how this could legitimately be tied to removing third-party cookies.
I agree that what you say should be true. But it is not, and I've already posted the sources to show it in my first message in the thread. Do you think the sources are fake? Or do you think that all those regulators are just joking around, and when Google does something they expressely forbid, it'll just be laughed off?
