I thought he was talking about the movie too. Never even heard of "Soul Man" the sitcom.
Anyways, as for the movie, people tend to forget blacks didn't begin getting respectable roles starring alongside white people until the 80s. Things were changing in the 80s, but there were hella stereotypical roles as well.
I suggest any young person go watch "Hollywood Shuffle," written, starring and directed by Robert Townsend