Free speech, and alternatives

Hello Lemmy! So, let's talk free speech, and social media networks. I'm quite curious why Lemmy and Raddle seem to be the only two (as far as I can tell) alternatives to reddit that are not as toxic compared to other alternatives, like Communities.Win, or ruqqus. I'm aware that Lemmy has a no bigot/hate speech rule, which is great. Raddle seems to support free speech also, but to an extent. How come some alternatives survive and others slowly decline?