Comment by digikata

I don't know, it's all probability in the dataset that makes one optimization strategy better over another. Git annex iirc does file level dedupe. That would take care of most of the problem if you're storing binaries that are compressed or encrypted. It's a lot of work to go beyond that, and probably one reason no one has bothered with git yet. But borg and restic both do chunked dedupe I think.