Yes the European Commission is operating its own Mastodon instance

You could replicate this workflow by replacing iCloud with Nextcloud and Time Machine with Timeshift.

The iOS app for Nextcloud allows the automatic upload of photos, you just need an account with a Nextcloud provider (or just host your own instance).

Timeshift is preinstalled on a bunch of distros, including Linux Mint, and can be installed on all other major ones. See https://github.com/linuxmint/timeshift for details.