A lot of people use it as an exploratory tool, they're also quite good at generating base images which you can bring in as the bottom most layer in PS and start iterating upon it.
The authors main complaint of turds, a rather crass descriptor, is really more about visual coherence of the overall image many of which are easily fixable if you have even a bare modicum of design/tech skills.
The author also seems largely unfamiliar with the most important tools of generative art which are image2image and inpainting. These tools make it relatively trivial to mask certain sections of an image and replace them with the background, insert new objects, you can even use things like controlnet to set up specific perspectives and angles using depth/segmentation maps.
You can do fast prototyping, storyboarding, conceptual art, mockups, etc. most of my friends who work in the professional design world are already leveraging these tools.