It’s actually SO much worse if you watch the whole interview. In my opinion the whole “you ain’t black” line took up too much attention in the national conversation, distracting from some other, arguably more problematic elements of it. He was defensive and noticeably hostile throughout. Charlemagne asked a simple question: “What are you going to do for black people.” And his answer was basically to brag about how much black people supported him and tell a bald-faced lie about how the NAACP endorsed him every time he ran. (The NAACP doesn’t endorse candidates).
Charlemagne’s critique of Biden was that he takes black people for granted. He spent the whole interview proving that correct.