How can I increase the demand for a brand with good quality advertising photos?
What affects this and what is the best way to do it right?

Look.
You first should understand what is moderation of images and how it affects the photo.
There are specific rules for photo moderation.
There is also manual moderation of images and automatic moderation of images.
And you should also understand that image moderation is necessary for business.
But to be honest, I would recommend you to read an article https://newmediaservices.com.au/image-moderation-for-brands/ on this topic because it will give you a much better understanding of how to attract a client with quality advertising images than I did.

I do not know much about it, but once heard in passing that it is quite important, but always missed the point of quality advertising (
I think it will definitely come in handy for me now.