Exporting originals just hangs for me. Opening or switching a photos library is basically hoping the Mac doesn't crash. Edits are locked inside the database, with no hope of ever getting them out. And god forbid you put the library on an external drive - never unplug it! It's a horrible piece of software.

I regularly back up my Photos library using rsync to prepare for the worst. From the files I see it looks like all the originals are there under /originals, albeit renamed to some UUID hash. However the EXIF data and contents seem to be intact. The number of files and their names are also stable. The database seems to be a basic sqlite DB.

I think it might make sense to extract the files directly that way, and try to see how the DB stores the original filenames. Might not be too hard. The edits though I think are applied "live" (at least for video) so it's probably impossible to get them out this way.

Dude get off the train. I run a self hosted immich instance for myself and some friends. I deleted all my Google photos from my Google account and I don't miss it. Alternatives exist. I love being able to automatically share my photos with my partner, or create shared albums that other people can upload into. All my photo syncing happens automatically via sync thing, but less technical friends use the immich phone apps and say it works fine for them.

I'm damn glad I never started giving my photos to the cloud, be it Apple or Google.