This isn't an issue of "nobody can use this" but an "everyone can use this", i.e. projects can use AI generated code just fine and they own the copyright to any modifications they do to it.

Think of it like random noise in an image editor: you do own the random pixels since they're generated by the computer, but you can still use them as part of making your art - you do not lose copyright to your art because you used a random noise filter.

That is only true for trivial projects that require no human creativity. For such simple projects not having copyright for it is not a big deal.