If I maintain a piece of software and everyone decides they’d rather use my version than develop their own, does that mean I control it, or does it just mean everyone is happy enough with my work that they’d rather use mine than do it themselves?

I say that Google does not care about you.

I don’t see how that’s relevant.

What are you gonna do about it, short of forking Chromium and going your own way, or maybe patching out their changes?

I dunno, maybe use of the many other Chromium-based browsers from groups that are already maintaining their own forks? Or use another browser entirely? I do both, actually.