alt Hacker NewsYou're absolutely right that artists can't stop themselves from creating, but I think that a reasonable amount of protection still does encourage more works.
Many works require a good deal of investment and time and if people had little to no chance of making money or breaking even on that investment a lot of works wouldn't get made.
Another nice aspect of copyright law is that it establishes where a work originated. Authorship gets lost in a lot of the things we treat as if they don't have copyrights. For example memes, or the way every MP3 of a parody song on P2P platforms ended up listing Weird Al as the artist regardless of his involvement. It also happens in cases where copyright really doesn't exist like with recipes and as a result we don't really know who first came up with many of the foods we love. A very limited copyright term would more firmly establish who we should thank for the things we enjoy.
IMO, copyright is something that should be shorter the bigger the media producer is.
The reason we need a copyright in the first place is to stop someone like disney just vacuuming up popular works and republishing them because they have the money to do it.
Disney, however, doesn't need almost any copyright to still encourage them to make new products. They'll do that regardless.
For an individual author, copyright should basically be for their lifetime. If they sell it, the copyright should only last 5 years after that.
A company like disney should get copyrights for like 1 year.
But also the type of media matters. IMO, news outlets and journalists should get copyrights for 1 day max. Old news is almost worthless and it's in the public interest that news be generally accessible and recordable.