Basically every back-up system does incremental backups, because indeed uploading or copying everything every time is kind of silly as you say. It's easy to go

Basically every back-up system does incremental backups, because indeed uploading or copying everything every time is kind of silly as you say. It's easy to go here "restic does that" but basically every other tool does that as well, so what "the best way" is depends on what other things you need, not on incrementalness. Personally I would use restic in your situation because I'm familiar with it already and it does what I need (I particularly like the encryption aspect), but that's not to say that borg, bup, rsync, or other tools couldn't also fit your needs.