It’s interesting that he uses “What” here, instead of “Who.” I’m not quite sure why – but it does seem like “What” may be SLIGHTLY more specific than “Who.” If someone asked me “Who are you?” I’d have a lot of answers. I’d likely start with my name, maybe include my nationality, likes, dislikes and general aspects of my personality. If asked, “What are you?” I’d go with “artist.” Unless I was being asked by an alien from another world or an animal – and then I’d go with “human.” Maybe even “human artist.”