Reddit has no community, unlike forums. It's strangers among strangers. It invites bullying, dunking, humiliating. Whoever drops the joke the fastest gets the most karma.
Instagram is quite similar and will recycle the same material for weeks. Take an old top comment burn from one reel and drop into a fresh new one, instant upvotes.
Twitter/X is just very public. Take a celebrity, say Paul Graham. Dude posts something random about rich people. Ha, let's eat the rich in public. Call Sam Altman a sociopath. Hate on Elon Musk on his own website.
Facebook has no downvote. You can say whatever you like and nobody will counter it. Controversial opinions thrive here. Fertile ground for anti-vax, anti-maskers, flat Earthers.
HN is well, https://news.ycombinator.com/item?id=40725329 It creates little containers around these kinds of topics. There's no way to downvote a topic either, and this one survived and rocketed after 14 or so flagged repostings.
tl;dr carrot and stick