Early in Ethan Hawke’s new film, Wildcat, a young Flannery O’Connor (Maya Hawke, Hawke’s daughter) tells a skeptical editor that she’s “amenable to criticism—but only within the sphere of what [she’s] trying to do.” That editor doesn’t end up publishing the work in question, perhaps illustrating that the gulf between what a piece of art attempts and what it achieves can be hard to bridge, no matter the affection the artist might have for the material.As O’Connor once admitted herself, a biopic about the author is a tall order. An epigraph of one biography quotes her: “There won’t be any biographies of me because, for only one reason, lives spent between the house and the chicken yard do not make exciting copy.” Indeed, she spent…