They already have a monopoly. The amount of people using FF is pretty small unfortunately. And there’s a bunch of sites that only test in Chrome and sometimes even actively “block” Firefox like here without making an effort to check for capabilities instead of user agent.

Plenty of them if you just search. Not sure about maps, but I’ve read this multiple times about YouTube on FF from reputable sources

Google doing the same thing with chrome, sabotaging youtube under Firefox, etc.

i want to see both of them fined heavily and best case forced to split some of their products out to separate companies (not sure how much that helps though)