Thank you for the feedback. I suppose this information suggests my search for a DAM solution is not over. Photos will not work. I was hoping some sort of hybrid filesystem and photos solution would have materialized by now. Rats. Such short sightedness on Apple’s part. Apple really is an enigma. So much effort has gone into helping to take a really great photo … and then practically no effort to support doing anything with the photo. It is as if they have forgotten that photography is an artistic creative work.
Maybe back to my earlier suggestion. Just a folder on an apfs volume with the photos contained there. I would need a way to migrate my Aperture libraries to folders of files and the XMP sidecar files and use RP for my workflow.