If they were gonna make Boo black, they should've used the Genie from Aladdin played by Will Smith. Or the Genie from Kazaam played by Shaq (reminder that Sinbad never starred in a movie called Shazaam).
I say that it's Not comically stereotypical enough. Should've been drawn like beginning of 20th century casually racist caricatures/cartoons. This one does not know if it's want to be a hentai black guy or an ugly bastard or something else.