The difference between a funny joke and a cringeworthy mistake is entirely dependent on your opinion of the person who said it and your willingness to recognize their point of view (which is not the same as agreeing with their point of view.)
Holding up part of a person’s statement as cringeworthy is a great way to shut down a discussion and discourage anyone else from defending them or even understanding what they were trying to say. It’s just another form of self-perpetuating uncoolness: once a person is labelled as uncool, then everything they do is worthy of mockery, even totally unremarkable normal things.
I don’t like it. Either say something about what’s actually wrong with what they said, or don’t get involved. You can win the argument without fighting dirty and you can leave it without insulting them on the way out. I don’t care if the person truly is awful. This isn’t about what they deserve; it’s about what tactics you consider acceptable, because that affects everyone you talk to, not just awful people.