It's the Guy Clark documentary based on the book. It's available to stream on the website only and on no other platforms and they have no plans to release it anywhere else. I had always been aware of Guy Clark mostly from catching him on Austin City Limits back in the 70's. I did not become aware of Townes Van Zandt until much later.
Their life's story I find very interesting, more so than their music even. The people that swerved in and out of their lives are an incredible cast. I'll be streaming it soon when I know I will have an undisturbed few hours to dedicate to it.