Private servers depend on the legalities involved, particularly the dissemination of source code that is copyrighted/trademarked.
Now if I was Disney, I'd release this code officially and prewritten to the fans as a thank you for our devotion and loyalty.
Just because they have to stop hosting a server doesn't mean a fan can't.
Also, I'm not sure of how easy it is to add these servers to an Playstation or xBox console.
They might have their own legalities to be observed on this issue.
Although, to be completely candid, I'm surprised with all the money Disney Corporation has, they can't just maintain the server permanently.
They just have to dedicate a small division to maintaining it and that would be enough for us to keep enjoying the game despite it's closure.