If you generate something with AI and claim you created it yourself you can easily be asked to reproduce a similar works again.

Asked by whom exactly? The Copyright Office? Are they going to ask for prove from every artist that requests registration for a work?

If you say you did use AI you should be able to show how much effort you are putting into creating the images

Or you can lie in your request. From the Compendium of U.S. Copyright Office Practices:

“As a general rule, the U.S. Copyright Office accepts the facts stated in the registration materials, unless they are contradicted by information provided elsewhere in the registration materials or in the Office’s records.”