[viraptor]

> Among the list of hate words in the lexicon ... is 'antiwhite'. Why?

Because the context it's most often used in is racists claiming that someone is against white people when other races behaviour is mentioned or when other races are defended. Just search for it on Twitter for lots of examples. (Not linking specific examples, they don't deserve the traffic) You'll commonly find it used together with whitegenocide, antisemitism and other stupidity.