Fallout New Vegas for sure. On Steam I have 467 hours logged and I played probably another 150 hours on Xbox 360 back in the day. If it wasn’t so hard getting Vortex working on Linux I’d be starting another 30+ hour save today.
After that is Project Zomboid with 460 hours but I feel that’s less shocking in a sandbox game.
I too would love a tbfp community on here. That and the Project Zomboid subreddit were the only ones I really browsed anymore.
EDIT: also there is a liminal space community on here. I haven’t quite figured out the link formatting yet but it’s on lemmy.ml ( !liminalspace@lemmy.ml ?)
True, I’ve seen larger websites go down due to Reddit’s “hug of death”. I imagine that even the limited blackout will take down the more popular instances.