The lack of black movies isn't that surprising to me in that vote results thread, given the likely majority on here and going off my experience with film majors in college. When I was a media studies major at college, the white students seemed to have no knowledge on any movies with a black cast outside of Do the Right Thing and Boyz in The Hood. I recall in my screenwriting class when the other black guy in there said one of the characters in my script reminded him of Pam Grier, someone asked who Pam Grier is and he looked at him weirdly for a quick nano second and then said Jackie Brown and then the rest of the class nodded their heads.
From time to time I mentioned other black films in class, but no one seemed to know what I was talking about except for me and the few other black students. It made it apparent that they definitely grew up just watching a certain selection of movies while we watched a lot of what they watched too, but a lot of black films as well.
These are the black cast films that stays in conversation with black folk in my experience:
Boyz N the Hood
Menace II Society
Dead Presidents
Set It Off
Poetic Justice
Friday
Baby Boy
Love Jones
Love & Basketball (Black women love the hell out of these two)