Bill,I am going to watch O Brother again. I wasn't as offended by the stereotypes and conventions, but I do see your point. There is a fine line between satire and simply making fun of people. There is a point where we have to poke fun at ourselves AND the sterotypes we developed, otherwise there would be no acceptable humor in the world. Did the Coen Brothers harm anyone or perpetuate a hurtful image? I really don't think so.
Sorry to take this conversation off on a tangent, a topic that has already been well discussed here on Mudcat.
You mentioned Scott Joplin above. There was a renaissance in ragtime music when the film The Sting was released a few decades ago. The film was set in the late 1920's or early '30s from my memory - long after ragtime had it's heyday in the U.S. There was no reason to have ragtime as the soundtrack for that feature, yet the music captured the feeling so well. It also enabled Eubie Blake to have a final step in the spotlight shortly before his death.
Granted the subject and style of both films were different. The point is that each film served to introduce a musical style to a new audience. Getting back to the premise of this topic, what we call it isn't as important as the way people enjoy it.
Ron