I've been trying to think about this! There's no sf/f aspect, obviously, but I think there's a lot to be discussed in terms of remix culture - the musical itself is obviously a transformative work.

ETA: Is that "enough"?! There are obviously other examples to be discussed - Wicked being an interpretation of book about a movie about a book lol. idk what the ~theme~ should be, though. That transformative works are & always have been a part of popular culture?