You pose some interesting issues here, Deborah.

I do not know for sure, but I think that fewer ordinary people buy original art of any type these days.

Maybe people have less disposable income for that sort of thing. On the other hand, those with money still buy whatever they feel like.

I think it boils down to contacts and luck.

When I ran a small art group, we would hang in a variety of places and once in a while, someone would sell a painting or a photo, (even me. ) We found the lack of interest discouraging.

My brother is a professional photographer, who has had his photos in high profile magazines, and who was a respected photo journalist in his day, but was really disappointed in the lack of interest in his work on the Getty site. You can check him out here https://www.tedrussellphotographer.com/. He was lucky enough to get a special show at theGovinda Gallery in New York because of his work on Bob Dylan, and because of a photo book on Dylan, featuring some of his shots. This was exciting, but not many books have sold.

Might you consider using one of those self publishing sites? The returns are not great, but they take care of all the printing.