You need an image for an ad. You write a brief and send it to an artist who follows your brief and makes the image for you. You make more detailed briefs, or you make generic briefs. You receive an image. Regardless, did you make that image or just get a response to your brief?

You want a painting of your dog. You send the painter dozens of photos of your dog. You describe your dog in rapturous, incredible, detail. You receive a painting in response. Did you make that painting? Were you the artist in any normal parlance?

When you use chatGPT or Claude you're signing up to getting/receiving the image generated as a response to your prompt, not creating that image. You're involvement is always lessened.

You might claim you made that image, but then you would be like a company claiming they made the response to their brief, or the dog owner insisting they were the painter, which everyone would consider nonsensical if not plain wrong. Are they collaborators? Maybe. But the degree of collaboration in making the image is very very small.