Ah, this is Thaler v. Perlmutter.
I seem to have picked up a reputation in these parts as being "pro-AI", so I'm not sure how my view will be interpreted, but Thaler is basically a loon. This case is not really over whether AI art can be copyrighted. It's about whether AI itself can hold copyright. ie, Thaler isn't arguing "I hold the copyright to this piece of art." He's arguing "my AI holds the copyright to this piece of art."
Since AI is not a legal person - it's neither human nor a corporation - this is basically an open and shut case. There is no entity capable of holding copyright in this case.
Since Thaler himself is explicitly disclaiming that he holds the copyright, that means the work in question has no copyright holder. Which puts it into the public domain. This specific piece in this specific circumstance, not all AI-generated pieces.
It's a commonly misinterpreted case.