Your hypothesis On the other hand is worth following if you have substantiating facts that back it up.
Basically; your experience is interesting but it isn't clear it applies here. Moderating a forum is not the same as maintaining real social cohesion when people genuinely disagree with each other.
When you have a single specific mechanism that can be applied to “real world polities”, then perhaps this discussion could work.
Otherwise you are talking about a federation of forums and the state of the art when it comes to effective moderation models.
I also recommend volunteering as a mod in one of these forums.
It’s a great place to see what’s going on at the point where the rubber meets the road- grounding your future ideas in tested experience.
edit: Since we came to recommendations, I would suggest you actually talk to some Nazis to see what they are all about. Not some troll on a board but people who show up to a rally of a far right party. Ask their voterbase why they are there.