[throwaway29292]

I agree with all of your points, except the last one. I don't think a shared ledger is required for interacting between multiple entities. We basically want a database that is beyond the control of any corporation - seems to me that a government-controlled database would fit the need.

The associated complexities and limitations with blockchain ledgers are a lot. The nodes must be propped up by large amounts of computing power, which only big companies/groups can provide, not individuals. And it's not as if the government can't be trusted, there are so many stock market indices & financial markets that aren't under anybody's control.