If anything I think that’s the biggest problem, is that he was using the slur as an insult AND as a synonym for dumb. ^^; At least, that’s the part that hella rubs me the wrong way.
I really just wish he’d at least apologize for the insensitivity of it all. ouo;; I know it doesn’t bother some people, but since I’m someone that has been called the r-slur in a hurtful and demeaning way on several occasions due to my mental illnesses, it really insults and to a minor degree hurts me that he would use the term so flippantly and without regard for the social sensitivity of the slur.