Firstly, I am going to preface this by saying, I was raised in Ireland, far removed from the racism of America.
As such, I would refer to others who have an understanding and vested interest and experience of this period or these particular experiences.
That said, I am experienced in those movies solely created for the titillation of others via extreme forms of suffering. I grew up with English films / authors depicting the abuse of Irish people and often exaggerated suffering for the mainly English audience. Whereas, the Irish would squirm, feel woefully uncomfortable and dislike the content.
I think this film is close to that margin.
It's pornified and the excessive suffering is only going to attract whom? It was too upsetting and bleak to persist with and there was nothing edifying or hope filled. The characters are 2D and so binary. It's difficult to connect to them. There is also uncomfortable stereotyping.
History is much more complex than this. People are too.