AMELIE sounds like a classic example of a "why" musical to me. A fantastic film with an iconic score, transforming AMELIE into a musical with its own distinct artistic voice will be a mean feat.
As for Jean-Pierre Jeunet's comment, I can understand why he might identify Broadway as a tacky theatre arena. Some choice examples aside, musical theatre on Broadway has become something of a theme park affair. People sometimes argue that this has to do with what sells but if we've learned anything from the past decade or so, it is that a jukebox musical or a musical based on a movie as just as much potential to flop in spite of the reputation of the band or film as it has to succeed.
Musical Cyberspace | a tribute to the musicals of Broadway and beyond.