The only problem? Despite the fact that the two share so much in common, the Coens made their character a self-centered douchenozzle whose talent for folk music is surpassed by his knack for mooching and womanizing. While the late Van Ronk was a friendly figure who encouraged and influenced young up-and-comers like Bob Dylan and went on to have a long career, his thinly disguised film version is a pathetic sad sack who clearly went nowhere.
This was a problem for at least some of Van Ronk's friends, who were unhappy to see the iconography of his life's work attributed to some fictional jackass. One folk singer remarked that they were "outraged that the Coens took such a colorful character and interpreted him as a doofus." How would the Coen Brothers like it if someone made a movie where their friends are sad losers being chased by Nihilists and almost castrated? Wait, never mind, the Coens did that movie themselves.