They are incapable of discussing this in good faith. It's gotta be like some kind of defense mechanism in their brain to try to prevent them from accepting the reality of the consequences of their decisions.
I think they absolutely know they’re wrong and have no other way out of the discussion. It’s a tried and true method of exiting a discussion when a troll gets caught trolling.
I mean, nobody is forcing them to discuss it on an internet forum. They could just... Leave? Shit I honestly wouldn't really care if they came back as another user name and pretended they were someone else, then just avoided threads about the topic...