IME when white people say racist shit about black people, it's still somewhat in code, or preceded by "I'm not racist, but..." There is, on some level, a recognition that "being a racist" is a bad thing and should be avoided, and an effort by the person saying this stuff to protect their self-image.
The shit I've heard some people say about Arabs/Muslims recently, same as I heard in the aftermath of 9/11, is really blunt and direct by comparison. Just complete insanity about what "the Muslims" believe, what they've done in Europe, what they want to do in the US, how we should just carpet bomb the entire region, etc. Just completely, blatantly dehumanizing. Half of the time I can laugh it off cause it's so outlandish, but only half.