I'm curious about this as well. My primary interest is the Caribbean, and while yes, that area varies a lot in terms of ethnicity, I do wonder if it "matters" that I am a white American female.
That said, the only prof at my MA institution that teaches Afro-American lit is a white male, and the only prof that teachings African lit (as part of a World Lit seminar) is a white female. I go to a medium-ish state school with no ph.d program.