The last X-movie made a ton. $748,121,534 worldwide! So Fox will be keeping that franchise for a long time unfortunately. ("fortunately" if you like the Fox X-movies)
I'm totally rooting for failure for the FF movie Fox is making. Would love to see Marvel get those rights back. Although I guess "rooting for failure" is the same as "rooting for Fox to make a FF movie". I will never ever ever forgive them for what they did to the Silver Surfer and Galactus. ...and to a lesser degree, Dr Doom.
I don't think I could ever root for a creative effort to be a failure just so someone else can have another shot at it. It also assumes that Fox would be willing to lease it out ala Sony instead of just sitting on it, which certainly hasn't been demonstrated.
So much work goes into a movie and, even it's not to my taste, someone worked pretty hard to make it.
I would also add that Marvel leasing out their big characters was not done at gun point. They may regret the deal now, but they didn't when they got paid. In light of the way things turned out, I am sure they have regrets, but who doesn't?