With Chromium being increasingly the only supported browser we soon won't have a choice which browser to use for certain websites anymore (e.g. Firefox).

That’s where I disagree. I think that if we do get an internet where Chrome is the only option and it sucks, we’ll get another browser option. Firefox for example went through a few years of being a bad browser but it has gotten past those hurdles. People are lazy and change is slow, but once it starts I think it is unstoppable.