Is there a method for automatic backup of Google Photos? Something that a script could do, without manually using Google Takeout.
Also, is there another service to backup photos that doesn't modify the data? I was thinking of using Nextcloud. But the prices for Google One are quite attractive.
https://github.com/mholt/timeliner is the script I referenced, and it does incremental backups. It is limited by what Google's API exposes, though, so what you get back is not what you uploaded: it's got many tags stripped, including GPS.
It's really best to back up the originals that are on your phone. SyncThing and Resilio will do that automatically to your NAS.