Not forever. But 75 years after the death of the creator by current international agreement. I definitely think that the exact terms of copyright should be revisited - a lot of usages should be allowed like 50 years of publishing a piece of work. But that needs to be agreed upon and converted into law. Till then, one should expect everyone, especially large corporations, to stick to the law.
> IMO any change to copyright law should not be applied retroactively.
Careful, if we were to shorten copyright, not doing so retroactively would give an economic advantage to franchises already published over those that would get published later. As if the current big studios needed any further advantages over newcomers.
It seems like it would make it more palatable to the existing franchises if their precious existing copyrights were not shortened. ("We paid billions of dollars under the assumption that we'd be able to milk this IP for 35 more years!") But anyway copyrights aren't going to get shorter in the near future.
When Mickey Mouse was created (1928), copyright was 28 years that could be reupped once for an additional 28 years. So according to those terms, Mickey Mouse would have ascended to the public domain in 1984.
IMO any change to copyright law should not be applied retroactively. Make copyright law to be what is best for society and creators as a whole, not for lobbyists representing already copyrighted material.