I honestly don't think it's that, at this point.
What if they sell the rights back, and the Ultraverse starts killing it in the movies or TV? Or what if they buy out the creators and the Ultraverse material flops?
The Ultraverse doesn't have the wealth of stories behind it that DC or Marvel do, so it's a far bigger gamble either way, and I doubt any suit at Disney wants responsibility for the decision.
So no one is going to make a decision about the Ultraverse either until they legally have to, or by some miracle, we get an EiC who cares about the characters