I think it would be possible, yes. Google has even developed a binary diffing system.

https://www.chromium.org/developers/design-documents/softwar...

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=538339

It would still not be pleasant for disk space. Ideally I want my OS as well as the VMs to be small and require as little ram as possible. I don't want to update my entire OS just because glibc had a critical bug.