UO forced many different types of players to coexist in the same world that simply do not mix anymore. You had peaceful dungeon crawlers and craftsmen coexisting alongside killers, rapists, thieves (wild that stealing items from other players inventory was actually a thing, probably unheard of in today’s MMOs).
The friction between these different types of players is where the magic happened, it’s what created real conflict and higher stakes in the world. When you stepped out of your house, there was always a risk that killers could be lurking ready to murder you and loot your house dry. And if you forget to lock the door, someone passing by will clean your house out for anything valuable.
In a way, old school UO was a true Middle Ages type MMO, everything since then has only grown more civilized, more enshittified. People don’t want to pay for a world that doesn’t give a shit if they have a bad experience. The truth is though there was no “bad experience”, it was all just an experience.