I don't get it. I read his comment as self-deprecating humor. If he had used white, jew, or whatever else may apply, it would still be self-deprecating humor,

I don't get it. I read his comment as self-deprecating humor. If he had used white, jew, or whatever else may apply, it would still be self-deprecating humor, which is generally non-offensive for the simple reason it applies to the self.