The neat part about the fediverse is that no matter how badly behaved a dev may be, there’ll be enough people to fix their behaviour and work around it. Look at mastodon, gorgon made a few questionable choices but glitch and all the other forks work around it and enough community servers exist that you could block mastodon.social and never miss a thing.

Just like with Lemmy there’s already kbin and countless other alternatives that all integrate with each other and enough community servers.

But with browsers that’s stopped being a thing a long time ago as the modern web is far too complex for small groups of indie devs to make their own browsers.