2 other big factors I think come into play:
1) Lack of algorithmic feed. Inflammatory posts/replies get a short lived moment in the spotlight, if at all. And then they’re gone. Algorithmic feeds change that as that short lived engagement is fed to more and more people.
2) Greater accountability to other users. I’m not sure why this exists more here compared to other social networks, but it seems to, at least from my perspective.