There hasn't been that much backstage trouble and keep in mind, all this "trouble" is pre-production. What you guys are amounting is the director leaving, Channing having trouble negotiating on a contract and the budget. To justify that, you all say that the movie was only made because of an interview Channing did. No, the interview Channing did gave Donner an excuse to make a film she had been wanting to do since X3 and would have done had Origins turned out well.
The budget isn't an issue. There are plenty of films out there with higher budgets than Gambit and less known stars that make more money. Take the budget out of the equation and you have two problems: Channing threatening to leave and Rupert Wyatt leaving. Of those, you can argue that Channing leaving isn't even an issue because for all we know he might not have even fully left the project because he negotiated a deal to star in the film, he was already slated to produce. Then there's Rupert Wyatt leaving, the only big issue and movies can still turn out good if the director leaves pre-production: Edgar Wright.
A big reason (not the only reason) you guys are making a fuss is because Fox is the studio funneling money into the film and not Disney. A lot of these reasons are valid, but I will say that it is a bit premature and maybe we should all wait before casting high judgements.