Original question by @StarvingMartist@sh.itjust.works
I’ll start, RuneScape, it used to be about adventure but now it’s about efficiency. Runner up, rust, very active community, but toxic playerbase and people usually abandon when a world isn’t fresh
Don’t Starve Together. Fatal flaw: it’s too hard for most people to want to play, and you have to play it repeatedly to get any good at it.