Important to note there are options.
I've been relatively pleased with the duckduckgo mobile browser. There are a reasonable amount of chromium forks that aim for privacy oriented browsing as well, although I don't have a specific one to endorse.
I guess in defense of Mozilla: it isn't really playing a different game in the browser space, they're just trying to mitigate some of the toxicity of ad revenue as a foundation. They're still a non profit hiring from the same pool as the tech industry money printing machine.
There's still a limited pool of support they have to pull from, and I like it better with them around so the big 3 don't have a total monopoly on browser architecture.
That said it's maybe the best example the model is flawed at the jump.
Ole Brent is going to find the terms of entry a lot less favorable.