back in like 2010 - 2014 the steam forums used to be a goldmine, specifically the "off topic" section. You had people asking random-ass questions i.e. asklemmy, people playing forum games, chatting about current events, etc. It was always super active and you'd usually get dozens of posts at any given hour. I remember commenting enough times that I got added to the "off topic regulars" steam group which was comprised of a whole load of people that I still chat with to this day
I think people who just contributed regularly and made good posts left for more well-run and well-organized sites. Lots moved off to discord where they could chat faster and more regularly. After that you were left over with what the forums were designed for: people who asked questions about specific games and software, rather than people contributing to a community.