@hideki i don't think it is art either, it is image generation. if you edit the AI image that comes out, then i would say it is photo manip. if you use the AI image that comes out within another art piece, i don't think that changes the art being art, it just means you used an AI tool in the development of that art.
for instance, if someone painted astronauts on a spaceship and they are looking down at a planet that was generated by AI, i'd still say the piece is a work of art.