I don’t think your objection holds water, then.
The problem wasn’t killing other players who didn’t want to PvP, it was…using a game mechanic that the designers hadn’t anticipated, in order to lower the costs of PvP?
What if he’d attacked other players and killed them and looted them and dismembered them, but then just stayed out in the forest and never went into town to sell his ill-gotten goods? Would he have played ethically then?
The fact is, the game supported PvP. Back in the old days when I played WoW, I played on a PvE server, and you could only attack other players who flagged themselves for PvP, or who accepted your challenge to a duel. There was no game mechanic whereby other players could attack me and steal my stuff, and even on PvP servers nobody could steal your stuff or cost you XP.
But Ultima wasn’t like that. It had PvP enabled by design, and nasty penalties for losing at PvP by design. This wasn’t an accident, this was designed into the game.
I understand that you wouldn’t like that game, and many people would agree with you, and I wouldn’t like that sort of game either. The flaw was that since UO was the first “modern” MMO it wasn’t appreciated how annoying this feature would be. And no modern game is designed this way, as a result.
But if someone had attacked you and cost you loot and XP you’d still be annoyed, whether they could use an alt to sell your loot in town or not. That can’t be the feature that annoys you. It’s the PvP when you don’t want to PvP that annoys you. The alt exploit is a red herring.
But you can’t complain that PvP was nonconsensual, because you consented to that when you bought the game. Seriously, you did.
And the big differnce between the PvP in UO and screaming epithets at other players, is that screaming epithets really is against the rules, and they will ban you for it. Even though there is no game mechanic that only allows positive speech over the voice channel. The rule has to be enforced by the admins. And if the admins ban your account for nonconsensual PvP then that’s fine as well, even if there’s no game mechanic that makes it literally impossible.
PvP in a game that allows PvP is not the same as harrassing another player.