Because people like the results of copyright, IE access to large amounts of resources including books, music, movies, and software that would not exist if there were not protections to ensure that the creators received compensation for their works.

I reject your hypothesis that nothing would exist if copyright didn't exist.

I wonder how humanity managed for so long without it, if that were the case. Or did we just not produce art or culture until we established copyright as we know it today?

Without copyright we would probably make mostly low-cost/small-scale art, of the type that can be achieved by a single person, and probably would not make big expensive collaborative projects like $100m+ blockbuster movies which are hard to bring into existence without a strong profit motive.

thank god. what was the last $100m+ movie you watched that you thought, wow, what a great piece of entertainment and/or art?

I could certainly do without big budget MCU slop, but Lord of the Rings? I am really glad that exists.

Copyright has (for better or worse) co-evolved with the technical ability to create effectively infinite copies of works, so I don't think we have any empirical data to prove or disprove this.

Right, we have no evidence that copyright helps promote the creation and distribution of arts, culture, or technology, and yet we restrict peoples' freedom to proliferate culture and art in the defense of it.

For recent or popular work maybe that kind of works yeah, for everything else though... I challenge you to find legally even early 2000s less popular movies or books, let alone older work.

The current copyright system is pretty terrible at keeping track of older content and the few ones that still manage to make it through have questionable rights holders.

Yeah it's pretty easy. I just went to a list of movies from 2001 by box office, number 100 was actually a cult classic now so skip that and I see the Tailor of Panama which is a less popular movie, steaming on Amazon https://www.amazon.com/Tailor-Panama-Pierce-Brosnan/dp/B000X... and i can get a copy on DVD with interlibrary loan. The Shogun miniseries from the 1980s has some renewed interest since the new version and it's not streaming, but you can purchase a DVD on a bunch of places and once again, I can get it through my library.

Also worth mentioning that free licenses like Creative Commons, MIT, and FOSS licenses like GPL are also all copyright schemes, as unintuitive as that might seem.

The removal of all copyright also means the removal of licenses that mandate free sharing and access. Two-way street, in other words.

Those liscenses, the GPL in particular, use copyright to fight copyright. The alternative to copyright is not necessarily a total free-for-all, you could legislate a replacement that works like the (A)GPL or CC BY(-SA). Require attribution and share-alike without restricting usage or distribution.

GPL uses copyright to ensure that software that makes use of GPL licensed code will be free (libre).

Even in a world without copyright protections, the printer story ( https://www.gnu.org/philosophy/rms-nyu-2001-transcript.txt ) would still have occurred, but there would be no way to ensure that it won't happen again with GPL licensed code.

Without copyright, open source code could still be locked up behind paywalls and compiled binaries. It is copyright that ensures that the law is there to force people to release their code.

The hypothetical legislation to ensure the GPL or CC-BY-SA works is copyright.

You could replace the license with a "contract" in the terms and agreements section to achieve the same effect? Contract law would apply, so I have no idea.