Essentially yes.

The GPL license is a way to take things that can be copyrighted and grant those rights to others with limitations (the limitations being the terms of the license).

However, the AI generated portions of the code are not copyrightable and so they're considered public domain and remain so no matter what. Once something is public domain it is always public domain, no matter where it is used.

In practice, if someone wrote a function by hand and then the AI added some error handling code, then that person has a copyright to the lines that they wrote while the lines that the AI wrote are public domain. The entire function can still be licensed under the GPL but the copyright owner would not be able to pursue you for violation of the license if you used the error handling code in another non-GPL work as that portion is public domain.

From a legal standpoint, since the code isn't annotated as to which parts were human written (protected by copyright/GPL) and which parts were not (and fall under public domain), it would be unwise to attempt to violate the GPL license terms by taking arbitrary parts of the code and releasing them without a GPL license.

The Free Software Foundation, the creators of the GNU GPL, has an FAQ that covers a lot of the details: https://www.gnu.org/licenses/gpl-faq.en.html#CombinePublicDomainWithGPL

I've seen a couple of Linux devs talk about how they just give a prompt to claude and walk away leaving it alone to spit out the code

While I share Linus opinion on LLMs, I think doing this shit is extremely stupid and lazy.

what is a proprietary line of code? how do you look at a for loop or uf statement and say "i own that". i can tell you that in all the huge applications i have worked on in the last 27 years, there isnt special proprietary code. there is proprietary data but not code.

the only time you really have proprietary codeis specialized code talking to a specialized device. so maybe a closed source driver.