I’m not describing Sam as an abuser, although he is a troll.
But “Sam does consistently does objectively bad things and of course I wish he’d stop and of course he’s said that he won’t, but sometimes he also does good things so why should he have to leave?” is the same bad logic that people in abusive relationships use to justify keeping their abusers around.
It doesn’t magically become a good argument just because the stakes are lower, and morality isn’t transactional. You don’t buy the right to be an asshole on Thursday because you were pretty chill and cool on Wednesday.