Duplicity, as you may know is not a deduplicating backup solution, it is an incremental backup solution, suffering from all the flaws and limitations thereof. If you happened to not realize the difference, I highly recommend this short but informative blog post from Backblaze: https://www.backblaze.com/blog/backing-linux-backblaze-b2-du...
I know the difference, but this way we have 4G volumes we could eventually burn to DVDs if we'd want to. No backup repositories, cloud storage solutions or new and obscure network protocols involved. Deduplication is also uninteresting for us because the largest part of our backup are SQL dumps. This is why we make full backups every time.
Also why would deduplicating be uninteresting when the backups are SQL dumps? That is EXACTLY the scenario in which deduplication would shine, because it would take each dump and find parts of it that are the same as the latest backup, finding the individual small chunks that have changed in those dumps, and only backing them up. Do you actually know how deduplication works? You might want to look that up more properly.
Until one of the statically compiled dependencies needs a security fix.
Then people realize why shared objects where invented.
One doesn't need an interpreter + supporting libraries to run a backup program. With a Go program one just drops a statically compiled binary in $PATH and it just works.
Anyway, I'm still using duplicity. It backups on rsync, ftp, you name it. Written in Python as well, unfortunately. Don't care abot S3 etc as I don't like loss of control over my backups.