sticking with regular Firefox for now. Mozilla is making some dumb decisions lately, for damn sure, but none that make me question using the browser without any "services", yet
It sounds like they just swapped out a more colloquial phrasing for a more careful legal phrasing that they were required to have in order to function normally. It doesn't sound as though anything's changing at the moment.
If that's the case it probably would have been better to add the legal phrasing onto it without removing the original phrasing. I am happy to continue using firefox as long as they don't break their promise.
The changes to how account data is processed will effect anyone who logs in with their account. If you want to avoid changes, you cannot use a FF account.
I probably don't count as Firefox is not my main browser, but I'm a very happy Vivaldi user. It's Chrome-based but comes with a great built-in (optional) ad and tracking blocker already, has tons of customisation features and makes it easy to disable all things Google (permanently, even).
I share your sentiment towards a Chrome hegemony, and I tried to use Firefox as my main browser a few times in the past. It's just that Vivaldi feels way more polished to me out-of-the-box. Some of the things probably just need some getting used to, but you know what they say about old habits...