One could argue that the problem is with me, or with the player, but I think that would be ignoring some of the cultural complexities that we live with. D&D is not played in a platonic world of forms. It is played in the real world with real people.
If a black person asked to play in my Dark Sun game with the usual Freedom entry point and we discussed it and everyone gave the okay, then maybe, but it would still be really uncomfortable for me. I would be thinking "Are we SERIOUSLY doing this?" the whole time. This setting was not written with a diverse player base in mind.