Here's what I think. The firing of Roseanne complicated things for Disney. If they were to re-hire Gunn there would be a strong opposition from the right about political bias. Why should Disney care about this incoming backlash? Because they have a brand to protect. Tweets about rape and pedophilia, such as those dug up about Gunn's past, probably don't give you the right to a happy ending over at the mouse house.
More to come ....
More to come ....