Trademark =/= Copyright.
They can copyright that fucking mouse all day long, the copyright on the older works is far overdue to reenter the public domain - especially when Walt, the fucking thief, took liberally from the commons to make most of his early successes.
Want to make a new creative work out of an old fairy tale today? Watch out you don't cross The Fucking Mouse's Army Of Lawyers. Nevermind that Sapsorrow/Cinderella is in the public domain, they'll come after you for making something "similar" to something they made based on the same thing.
Same thing for half of Hans Christian Andersen's catalog, same thing for so many songs where they blatantly stole the melodies from earlier-era, public domain music, and on and on and on. Disney and the copyright cartels see the public domain, not as a common resource for all, but their personally owned little idea-mining zone and that needs to fucking change.