That's true, but its a deeper problem with that. The moderation is a sort of "in protest" form, with lots of deliberate "blind eyes" and slow action so they don't get deplatformed by the app stores etc.

Beyond the moderation, these sites have the problem that they are inherently set up as a sort of opposition haven -- "we're twitter for people banned from twitter!"

This results in a phenomenon Hank Green calls the "worst people problem"[0]. I'm not a huge fan of the judgemental term, but the core idea is similar to pointing out the inherent contradiction of, say, an anarchists' society. You end up with a userbase that is defined by its desire to flaunt rules and reject any normative standards.

[0]:https://threadreaderapp.com/thread/1348101443404787718.html

(somewhat related and worth a watch: Folding Ideas' 2017 video essay about YT alternatives. Alt platforms have had inherent problems even before the more recent political bent: https://www.youtube.com/watch?v=r3snVCRo_bI)