When ape cultures grow to large, eventually there is a dispute and you get a tribal split. Some of the tribe sticks with the original leader, some move to the new tribe. Researchers have found that this is related to neocortex size, and that if you take human's neocortex size you would reach tribes of 150.
Article comment sections are tribes. If those tribes get to be beyond 150, you reach natural tribal splits, but with no way to actually split. Hacker News comment sections are a tribe. Sub-reddits are tribes.
We're all fighting Dunbar's Number. We're all going against the grain. Incivility is guaranteed. Other than going to a smaller website or creating another sub-reddit, I do not know of a single community that actually takes Dunbar into account.
And even if such a comment website was created, then we get the opposite problem. If we segregate everyone to their own perfect 150 person tribes, then we get bubbles! We get the antivax tribe feeding their own biases with no checks.
So not only do you need tribes, but you need to find "model tribes" that the other tribes can look up to. So you need tribal networks as you wouldn't want to centrally control that.
It might be a good idea, that when speaking outside of your tribe, you are communicating not as yourself but for your tribe. So people don't see allochthon talking, they see Hacker News talking. If your tribe did not back the comment, they could decide to hide it themselves. If you don't agree with that, that might incite a tribal split. If other tribes decided they didn't like that comment, they would down-vote your entire tribe.
Being part of an elite tribe might be a signal of social status in much the same way that historic Venice Coffee houses and the conversations and inspiration that came from then led the Art world. And as each tribe is small, each person within the tribe is personally accountable.