According to the boys at CinemaBlend, quoting a longtime scooper “in the know”, it’s less about Darren Aronofsky not wanting to spend a year overseas and away from his family, but more a matter of control. By which I mean, Aronofsky wanted and needed “total control” over the movie to do what he does, but Fox would not give it to him. This, despite the fact that his last movie won a ton of hardware, along with a Best Picture nomination. Apparently that didn’t sway Fox producers one bit.
We’re told that after his last movie earned a Best Picture nomination and won Natalie Portman an Oscar, [Aronofsky] made his demand for the total control over the film that he’d wanted all along, the kind of control Christopher Nolan now has over the Batman franchise at Warner Bros. They tried to give him more money but that wasn’t what Aronofsky wanted. In response to his demand for total control, our source says, “the producers pretty much told him to walk.” So this morning, he did.
So there you have it. This certainly sounds like more of a plausible reason for the split than Aronofsky just wanting to spend more time with the family, which was the excuse used by the director and Fox in their official press release announcing the separation.
“Family time” is a politician’s excuse for quitting; “Creative conflict” is the Hollywood way.