Okay, you said a lot here, so forgive me for focusing on the parts of that post made hit reply. First, Disney paid an undisclosed amount of money (in other words, something obscenely steep, probably in the hundreds of millions, maybe a billion dollars or more) for the world-wide exclusive Avatar rights, including ALL of its sequels. SO, the rights are theirs and they ponied up the big bucks for it. They can't return it for a refund or exchange it for the rights for Terminator, for example.
Second, just because we haven't heard anything doesn't mean they're having problems or its not happening. No one heard about Hyperion Warf for a long time after it was announced, but it turned into the much bigger and more ambititious Disney Springs, for example. Disney announced a couple of years ago a project called Flamingo Crossing. I heard people compare Avatar to that project, saying, like Flamingo Crossing, Avatar is dead. Truth is Flamingo Crossing is anything but dead. They had to announce it much earlier than normal because of a legal complication that forced them to disclose their plans for that far in advance. The truth is development takes time and Flamingo Crossing, like Avatar, were in the very early planning phase when announced.
It kills me each time when I see people here just assume an announced project was dead just because they haven't heard developments on it for a while. No leaks even. Well, hasn't anyone figured out that maybe security has been tightened? Apple has doubled down on security in an effort to stop leaks. Disney's CEO is also Apple's chairman of the board of directors. Iger was definately in the room when Apple decided to double down security. Don't you think he probably thought, "Hmm, we need to do the same thing at Disney..."? I would wager on it, considering we here think leaked information is "normal". It's far from normal. It's illegal and we here encourage it!