I mean common instrumentation available is: yes rating button, real name, mandatory picture, verified picture, verified identity, friends feature, high visibility of friend feeds, public-only communication, admins... Social web services of any sort implement some combination of these.

Reddit implements only a rating button as far as I know. (Sorry not a regular user, but I bet it has one or two other mechanism to prevent people from posting complete trash regularly.)

Actually before Facebook become popular, almost all social media platforms were practically anonymous. In the middle of the 90s this worked IMHO quite well because only few people had access anyway. So you could see that Forums, chats etc became trashier. Facebook came up with real identity profiles (real name, picture etc etc), so the quality of content and contacts got exceptionally high for social media.

I guess another leap in this direction might become necessary. Not sure what this would be, but if we don't want state to babysit our social networks, the site operators better come up with innovations in that area.