I've had this idea for a while. Happy to see it get a wider audience.

The problem I have with blockchain-based "currencies" is that they are fiat currencies. Their value exists only in the minds of their believers. Gold and silver value also exists in the minds of their believers, but they have historically been valued by all. So I would much rather think of the blockchain as a triple-entry ledger to keep track of a real commodity, like gold or silver, rather than imagine that those bits have value all by themselves.

I, too, realize that if you don't have the gold, you don't have the gold. But it's still worthwhile to put some of your holdings in the hands of a blockchain-backed storage service, so that you can easily use it for global trade.