I would actually ask what's in it for Sony under that theoretical scenario. Sony giving up production rights and retaining distribution rights in perpetuity (a la Universal and Hulk) would mean they are giving up something they have now in exchange for a little better deal on the distribution front. Thing is, though, Disney/Marvel would block Sony out quick. There would be no more Spider-man titular movies and they would just proceed to use the character and the rogue in other character's movies and in ensembles. Marvel kinda did Planet Hulk, at least references and overall theme, in Thor Raganarok. That's the reason why I would hope they would focus on getting that back from Universal so they can give us World War and Immortal Hulk movies.