[bleair]

The motivations are different, but I think wikipeida is an interesting example where editing / moderation does (mostly) work. Again, I can't see how that could ever work on twitter, but wikipedia is the only large-user-base example of "social media" that isn't horrible.

[ehnto]

I think that is because every contributor is responsible for the whole, and thus they are also all moderators, and all responsible for any content digressions.

If someone posts a hateful tirade on twitter, it's no one else's responsibility but twitter's really. It's their account, and Twitters platform.

Of course, if you gave Twitter uses the ability to self moderate, it would be an absolute mess.