When the issue at hand is something like "I think black people deserve the same rights as white people," no, no one is ever going to convince me of the opposite. There is literally no point to me listening to someone who has that as their position (and you're damn right I don't want them convincing the audience either). Same with a number of other prominent issues at stake today.
So if someone comes at me with one of those positions, and doesn't seem, from the outset, to be already seriously on the fence, or to be presenting extremely easily debunked misinformation, yeah, I'm going to nope out of there. It's not worth raising my stress level to argue with that type of person, with or without an audience.