I recall reading a study (years ago, so do not have a link at hand) that considered externalities of copyright and concluded that about 10-15 years would be a reasonable tradeoff between creators' and society's interests.

10-15 years after publication, though, not after death. Also, nonrenewable.

Is this the paper to which you are referring? https://rufuspollock.com/papers/optimal_copyright_term.pdf

12

Ok, 4.

Are we talking months, or hours?

While it sounds nice (from a consumer's perspective) to have no copyright at all, it would prevent a lot of media from being made, e.g. expensive movies.

Movies for well-known franchises could possibly be financed through crowd-funding, but that would make it hard for production companies to make bets in new franchises or directors.

If you can't make money in 20 years for a movie, it's never going to make money.

Everyone's good with this as far as software goes too, right? All apps go public domain after 20 years of release?

If copyright were shortened to 20 years as suggested, it would be legal to freely distribute copies of Windows 98 and Photoshop 5.0. I doubt that would make a dent in sales of Windows 10 or Creative Cloud. Newer versions of both would still be copyrighted, and there would be no obligation to release any unpublished source code.

Open Source, more like. A 20 year old software in vanilla state would likely just not run at all in current hardware.

Sure, but that's what projects like QEMU/DOSBox/other emulators and compatibility shims are for. There's so much abandonware out there, especially games that are stuck in licensing limbo that can't legally be acquired - and it's only going to get worse going forward as things like licensed middleware, soundtracks, etc. have been thrown into the mix with their own headaches.

@redbeard-- how about VAX/VMS for example? I believe licenses are still being sold for millions of dollars...

Probably for the up-to-date version. Not the 20 year old version.