Lemmy.world is run by the same people as mastodon.world. I guess a lot of users from mastodon.world went to Lemmy.world and the rest was word of mouth.
Yeah, people just want a “generic” place because they generally don’t want to be pidgeon holed. I have nice and inoffensive lemmy.world and lemmy.today accounts because of this. I’m basically a vanilla NPC in my life and “sh.itjust.works” is simply too spicy!