Most people I know don't have any concept that copyright does or should expire. They think if Disney makes a movie, it's Disney's movie forever.
Nonsense. Disney would make plenty of money on Frozen 17 with Snow White in the public domain. Extreme copyright lifetimes just stifle public creativity and are an excuse to implement draconian and authoritarian practices.
Though I'm not sure that Disney would have been deterred in every case.