The big problem with FLoC, as I see it, is that it makes fingerprinting vastly easier. Your FLoC bucket narrows you down to one of several thousand users, rather than one of several million, and that's before fingerprinting applies.
Ironically, it seems that FLoC makes user tracking easier, not harder.
I see no upside in FLoC for me as a user, and plenty of potential downside. I'm glad I use Firefox.
Without making any drastic changes to my browser to intentionally inhibit fingerprinting, I already have a unique fingerprint according to https://coveryourtracks.eff.org/, so this honestly doesn't signal a change to me at all. I just run uBlock Origin to block trackers/ads.
I have the same. And the majority of what makes me unique, at least according to the EFF website, is absolutely not needed for 99.99% of the websites I visit.
Ironically, it seems that FLoC makes user tracking easier, not harder.
I see no upside in FLoC for me as a user, and plenty of potential downside. I'm glad I use Firefox.