We are unlikely to see a large-scale movement towards self-reliance by users, or any government in the U.S. or Europe taking this on directly. Instead they will penalize companies until they do it.
So the companies that got big are ending up with the governance job because nobody else wants it. Mostly they started with semi-libertarian philosophies until they found that social media does not work that way and someone needs to handle the filth. And a lot of companies that started out with online forums (like newspapers) decided that it's not worth it and shut down their forums, so there are fewer players.
This makes it convenient for scapegoating. We can blame the big tech companies when they get it wrong, because we don't want to do the work ourselves.