Some of the "drama" feels forced but the music just flows from the story. Boseman's illness probably contributed to his appearance which is spot on for his character. The other members of Ma's band are solid hard working actors just as their characters are solid hard working musicians.
The movie started slow for me and, as I mentioned, the drama and conflict felt contrived. But it is well worth a watch. Sad that this could ensure a Lifetime Achievement award for Boseman, a talent gone too soon.