This one would be cool, especially because no entity can claim ownership of the IP. I'd love to see how people adapt to the idea of a "non-franchise" where you pay attention to the continuity and works of a specific creator, but not because the franchise itself has any official continuity.

This is already true of things like Sherlock Holmes and Dracula, but I can't think of a recent fictional world where, from the get-go, there was no official canon.

That would be interesting