The article opens with "a shocking new tracking admission from Google, one that hasn’t yet made headlines, should be a serious warning...", but I can't figure out what they're referring to? The article discuss FLoC, but I don't think that can be it: that's had a lot of coverage (and the origin trial is on hold in response to feedback).
(Disclosure: I work on ads at Google, speaking only for myself)
(Disclosure: I work on ads at Google, speaking only for myself)