On Intentions and Censorship

Why can’t a white person say aloud certain words written by a Black person?  Why can’t a white person repeat certain words in the lyrics of many rap songs made popular by Black artists? 

In my view, the deciding factors are the intentions of the white speaker, the Black writer, and the Black artists. It seems here some people don’t care about intentions and their own intentions are to categorically censor another human being. What authority or moral principle is such censorship based on?

I don’t think such blanket censorship belongs in academia.