Alex wants to inoculate his audience to the possibility of them hearing people accuse him of being a racist. A lot of his content is flagrantly racist and he understands that on some level. So he knows that it's inevitable that people who listen to his show will end up hearing things from other people who say he's racist. That is racist as shit. I agree with you. The goal here is for Alex to take a completely obvious example of something that isn't racist, but includes a trigger word that he can pretend someone will call him racist for saying, in this case, black. He pretends that people will say he's racist for saying things like black ops, so if a listener hears someone accuse Alex of saying something racist, their immediate response will be like, oh, sure.