Earlier quoted context omitted.
What if such a system was implemented using IPFS[0] (or similar) for storage? [0] https://github.com/ipfs/ipfs
I'm surprised all package managers don't use an IPFS-like system that uses immutable state with mutable labels and namespaces. Now that IPFS exists, and provides distributed hosting, it's even easier.
You can experiment with ipfs-backed git remotes though. That's already possible.