This is the absolutely critical point that people are either too privileged to have ever thought of, or too disingenuous to admit.
Yeah, I'm a relatively wealthy (by global standards) white guy of European descent. You can joke about genociding me and I'll laugh because it's a ridiculous thought.
People who grew up genuinely at risk of genocide, or who had recent ancestors killed, don't see that same joke that same way. Worse, the people making those jokes about populations that are currently being exterminated are just doing the old "hey I'm a nazi, ha ha just kidding, can't you take a joke" thing. Which, great, free speech. But at some point if you're goose stepping in jest on a daily basis, that's just who you are.
Kurt Vonnegut said it: we are what we pretend to be.