I kinda think Twitter-culture made “forums” lose currency and people just seemed to stop talking about them.
Twitter is largely a flame-fest/dumpster-fire and at some point, that behavior carried over to most other online “discussion” media. After a bit the SL forums were “unlivable”.
Things seem to have calmed down. I’m hearing that “while I was away” LL did some cleanup that seems to err on the side of Overkill - but things seem calmer.