k, just watched the vid for Gitchain. This scheme is addressing availability and per Brewer's CAP theorem, full availability and consistency* in a distributed system is impossible. [Shades of momentum/position here, btw .. ;)]
Even (or specially) in a P2P system, CAP holds. Partitions are unavoidable. One must either pick full consistency (but sacrifice availability), or, insist on full availability but sacrifice consistency (which in case of a Git like system, means you may not have access to the latest commits.)
Vector Clocks or BC type systems, carry the entire state and thus face the same issues that keeps insects down to a certain size. It can not scale indefinitely.