Facepalm

Not really, he has a stereotype of what a Black person acts like, that includes saying the n word.

He can't comprehend there are some people who are both Black and find the word distasteful. So to him if a Black person won't say it, then they're not Black.

It's perfectly logical when looking at it from a racists viewpoint. And if you haven't noticed there's a lot of them these days, it's important to understand how they think, so you can do risk management on what they're trying to do.

Do t just write them off as "evil" and illogical because that makes it harder to fight them. Their logic might not be based on facts or critical thinking but there is a type of logic there. Flawed logic is still logic.