A lot of Facebook is people with their real names posting vitriolic bile in full view of their entire real life family and friends.
I don't think Real Name policies are the solve. It still doesn't matter when you interact with 1,000 random real names in the comments whom you'll never have to reconcile with in real life. The latter is the important part. The medium itself reduces people to content and encourages context collapse.
Read what I wrote again. It's not just names, but names and contact information.
There is already typically enough information to contact people's family, employers, or (as was popular / horrific for a moment) send SWAT to your house.
Real names and contact info don't stop people, and worse, they expose everyone to these tactics. If I read a comment of yours that I don't like, I can asymmetrically punish you by signing you up for spam or worse, and you'd never know who did it or why.
We do need solutions where people stake value (like their real identity) and have to contend with real repercussions. But I don't think identity like this actually gets us there.
The reason Old Internet felt better is probably still the solution: smaller online communities, where you have a sustained presence, and getting account banned would meaningfully disconnect you from your social group.
Algorithmic feed / Front Page effect seems to be the main cause of the problem, since you get a flood of people disconnected from the community or topic, having no context, piling on, then leaving.
YouTube seems to have recovered from being a toxic pit and now manages this well. But I haven't found a good writeup of how they made the shift.