... it's not closing until January 1. Previous reports suggested it might close as early as November (to make way for Back to the Future)... and certainly, Hugh Jackman has a film career to return to and was never going to stay indefinitely. Given the difficulty replacing him with someone of equal star wattage—and the generally mixed reviews—I'm not convinced that its full-year run is a sign of Broadway 'suffering' so much as this production's predictable lifespan.
(Which is not to say that Broadway isn't suffering... I just don't see MM's closing as evidence thereof.)