Thanks for the question!
To put it briefly; all AI image generation has to pull from somewhere, but the models and processes we use have been specifically chosen to be much larger pools. Then, we tailor the process to be a more 'generic' anime style or genre rather than of or close to a specific artist or art style.
We've seen plenty of VNs and games that are clearly using AI art, and we thought it was wrong not to advise that we do use it. Additionally, all models and processes are credited where required. Basically, putting in the time and work to ensure we're not ripping anyone off.
Hope this helps!