This is definitely what Google would like you to believe. Considering indeed all other browsers have killed third party cookies, Google legally very well could as well. But they'd love you to believe they must provide a way to invade your privacy.
The issue regulators had was Google retaining special access to user tracking, they have no problem with Google removing their own ability to track as well. Of course, that doesn't buy Larry and Sergey's next yacht or private island remodel.