I heard that it is pretty blatant in it's historical revisionism vis a vis the political inclination of the black panther party, but I haven't seen it to corroborate that.
Edit: okay, after reading the directors interview with GQ and reading some other comments it seems like i might have been completely wrong lol. Very excited to watch it now
Hoover said the panthers were the greatest internal threat to the United States in a letter like you mentioned.
I am scared to watch it because I get extremely inspired by Hampton