I agree with MB. So many are second-rate films to begin with.
And it at least appears to be musicalized for no other reason than it has a built-in fan base and a good "recognizability factor."
It's rare that you see something like "Grey Gardens" or "A Little Night Music." They were based on well-respected films, but they were never big fat hits like "Footloose" or "Legally Blonde."
I think it's easier to get backing for a show if people already know the subject matter. So it's not necessarily that writers are picking only the obvious (even low brow) choices... but those are the ones that are making it to Broadway, because they arrive with people knowing what it is... and more willing to buy tickets.
With prices over $100 now, it's risky betting on a show you know very little about. People are more likely to wait for reviews and word-of-mouth on original or unfamiliar material. Sometimes TOO long, and a show might close. With a high profile subject, there is a guaranteed "advance" to some degree.
"Jaws is the Citizen Kane of movies."
blocked: logan2, Diamonds3, Hamilton22