This is the bane of web forums. As the lowest common denominator for posting an opinion, they tend to get the lowest of postings, and require an enormous amount of curating to keep them reasonably civil. This is why many serious discussions still take place on things like mailing lists, where the curation requirement is dramatically lower. Pretty much any form of internet communication other than web forums keeps the curation requirement a lot lower.
I used to be the top contributor on a canyoning forum that was on Yahoo groups, but everyone used as a email list. Literally zero moderation was ever required for over a decade.
Then it slowly moved to a Facebook group as Yahoo Groups died in popularity.
You guessed it, complete shit show in terms of moderation, and some banned people started a competing Facebook group that was supposed be "moderation free", but ultimately had similar issues, and I think a third group sprung up as a result as well.
At one point I was banned from the original Facebook group for a completely innocent post. My crime was asking why my post vanished. The founder decided to step down after that incident.
Also got threatened with a ban from the 2nd group for being "insensitive".