I disagree with you too.
They never offer you the choice. The turn it on by default, and do not even inform you of how or where to turn it off.
Giving users a choice would mean an option during install or first run.
- How should Firefox incorporate AI on this profile? A) running when FF starts B) turn on AI at user request at time of request C) disable all AI on this profile
That to me looks like choice. I do use Firefox as my main.