I was also a very active user of traditional forums but, in my experience, small subreddits (when I was on Reddit) were a decent substitute, since posts could stay on their front page for several days. The thing I missed most wasn’t actually the format but the community. I knew the people on the forum I posted on the most.

There was the guy with a kind, insightful take on controversial issues and a fetish for women with more than two arms. The active duty marine who reliably posted harsh truths. The feminist I didn’t get along with at all despite agreeing with her about most things. The dedicated father who bought real razor wire for his daughter when she wanted a UN-peacekeeper-base themed birthday party. The very determined conservative who defended his position no matter how outnumbered he was and once bragged that he had given his wife several dozen orgasms in a row…

I suppose I was the young man with strange views about what was or wasn’t fair and a great deal of anger over any perceived unfairness. (I don’t think I was particularly well-liked.) It’s hard to find that sort of thing on the internet these days.