Public domain absolutely exists in the EU.

Hmm. There was some kind of issue with that in the EU that led to the creation of a Creative Commons license, IIRC. Maybe nonstandardized handling of stuff not under copyright. I remember that in the US, putting something in the public domain wasn’t an issue, but in at least some of the EU, it was important to use Creative Commons instead.

I think that something not being under copyright isn’t analogous everywhere.

googles

https://en.wikipedia.org/wiki/Public-domain-equivalent_license

In 2009, Creative Commons released CC0, which was created for compatibility with jurisdictions where dedicating to public domain is problematic, such as continental Europe.[citation needed] This is achieved by a public-domain waiver statement and a fall-back all-permissive license, for cases where the waiver is not valid.