Whatever you think of de Sade, he was a complex figure and we should not look for easy answers with him. He was, strangely perhaps, against the death penalty, and he was never put in prison for murders or anything like that.
Fear can be like a prison. It is, however, a self made prison. Many are imprisoned by fear. No one else can liberate them from this prison. Others may inspire them but they must liberate themselves.
They're not supposed to show prison films in prison. Especially ones that are about escaping.