Ironically Marvel might be using a black actor to play Kang just so they don't look like, well,
Ridley Scott when they revel he was Rama-Tut. It might not necessarily be in the spirit of inclusion but rather insurance against looking tone-deaf cause they plan on doing that particular storyline down the road.
So, agreed there, folks thinking this means a black Reed Richards might indeed be sadly mistaken.
X-Men is another can of worms, though. In order to see black characters they
would have to race bend them, especially black male mutants. Either do that and face the ire of fanboys online, or don't and get the movie-going public going "So, its Storm, that's it for black characters?"
I'm curious how Marvel will handle it. Morbidly curious, but not enough to lose sleep over it.