I created a simple PHP script that reads the OS X Photos library (SQLite) and creates a folder with symlinks to the original photos organized by the month the photos were taken. This folder can be then sent to a local NAS server, Amazon S3 or Glacier, Backblaze B2, etc. I use it to avoid adding everything to the shared “Family” album on iCloud Photos.
I’m still amazed by how simple it was to access all the Photos metadata.