Read the book. In the movie, Ron Howard tried to dodge the very penetrating issues Vance was raising on the sociological, political and cultural front. I assume that Howard, who is a conventional Hollywood liberal but a pretty decent guy who makes mainstream movies, recognized that Vance was too explosive for Hollywood to handle. He centered the movie on the underlying family drama while largely sidestepping the wider issues. The book is excellent. The left hates it because Vance insists that poor people have agency and that escaping the poverty trap is likely to require changing behavior.
I think my wife read it and therefore it is around the house. It sounds like I should find it and read it.