Specifically, I've got a big honkin' pile of photos stored on an online storage space, and I want some kind of software that lets me share links to a pic, or a group of pics, or a folder, etc ...
... and here's the crux ... without making extra copies of the pics ... just has renamed, custom-permissioned links to the original pic(s).
In database terms, I want something that gives me Views of my photo collection.
I run my own Nextcloud instance, which is close. It has very nice, very granular photo management and sharing capabilities ... but as far as I can tell, whenever I share a pic with someone, it actually makes another copy of it for the shared instance. If I share the photo 5 times w/5 different people/groups, then suddenly, I have 6 copies of the pic.