You're right if course. What I mean is, would it hurt to just package firefox? Or is it really that important for some developers to have access to Chromium or Chrome?
And I appreciated that it had Chromium (which it packaged itself) as I also used it.
I doubt that any distro would increase it's user base by not packaging Chromium, as you could just not install it if you don't want it, like with everything else.
But that being said, nothing stops you from voting with your feet and switching to a distro that makes it difficult/impossible to get google chrome and/or Chromium if that will make you happier.
Additionally, in my case, Chrome is the only browser that works with the Web Serial API, though other Blink based browsers ostensibly should support it.