AI Art Generation is a form of Conceptual or Post-Conceptual Art.
Allow me to explain. Here is a definition of Conceptual Art:
Art in which the idea or concept presented by the artist is considered equal to or more important than its appearance or execution.
How it fits:
If an artist has an idea of what they want to see but aren’t too worried about the outcome, so they create a prompt and regenerate over and over again until they get something they like, that would be Post-Conceptual Art. See John Baldessari’s post-conceptual piece “Throwing Four Balls In The Air To Get A Square (Best of 36 Tries)” from 1973 as a non-AI related example of this.
If an artist has an idea of what they want to see, does some research, drafting, exploring and carefully designing and refining a prompt, reframing, regenerating parts of it, editing and post-processing the image, etc. that would be Conceptual Art.
This flows with my belief that art is defined by any individual who views it as such, either the artist or the viewer, and not the process by which it is made.