So, if you make art with AI, at least at the time of writing this, I believe it is all public domain. Not all of it. My wife makes and sells copyrighted AI images. To do that, she pays a higher subscription price to the AI engine - kind of the "pro edition" - otherwise the TOS of the AI engine say they own the image you create. The image creator can release the content into the public domain, that's their choice. But much of it is indeed copyright protected.