I would say to keep the moderation active, and focus it on encouraging reasoned posts, while striking down posts that go too far in a personal direction, ad hom

I would say to keep the moderation active, and focus it on encouraging reasoned posts, while striking down posts that go too far in a personal direction, ad hominems and so on. Start with warnings, scale up to temporary timeouts, bans and eventually permanent bans. Strike down extremely hard on any kind of doxxing or threats. Have moderators cover only a few subforums, so they don't get stretched too thin, have the moderators/admins confer internally on cross-forum issues and bans. It does require a competent moderator team that knows when to let discussions run, when to gently nudge people towards more reasoned debate, and when to swing the ban hammer. Reddit was absolutely not perfect at any point in time. There were countless cases of power hungry mods in their own little kingdoms, doxxing, inter-subreddit fights and exceedingly virulent hate subreddits that specifically did their best to hurt other people. That's not debate, that's bullying and in many cases criminal.