That's true, but to my knowledge no one has ever made a film out of a Broadway musical that lost as much as $20 million (despite all the Tony wins in a very weak season) in its original run. Even the revival lost money, despite being a stripped down (yet effective) version.
Norma is supposed to be 50. Close is 74 and looks it. Zac Efron and Jake Gyllenhall would be fine as Joe, but not opposite Close. A pairing like Gyllenhall opposite Michelle Pfeiffer might work. She's 62, can pass for 50, plus still smoking hot (IMO and I'm gay).
However, as much as I have enjoyed the musical -- I've seen it 5 times: on Broadway with Close, in Toronto with Diahann Carroll, 3 times in Chicago -- the musical is not in any way as good as the '50 film. I assume a movie version of the musical will easily cost in the range of $80 -- 100 million. It's hard to imagine any film company coming up with that kind of money given that the stage version has never been profitable, unless Lloyd Webber wants to foot the bill himself.