You can trust or enforce the shipment of goods monetarily if the money only flows when contracts are fulfilled. That's the whole point. People don't get paid unless they send goods. They don't have to send goods until money is provably locked in a form of escrow that can be settled immediately upon the arrival & inspection of the goods. With gold you can either ship it first & take all the risk, or they can ship the goods first & take all the risk, but there's no way to balance the risk. And the added cost of shipping gold doubles the cost of the exchange.
Discussion
Well you *could* add a third party escrow service who receives the gold and then forwards it along, and actually triple the cost
And arguably increase the risk by introducing another party to the transaction. You could be screwed by a trading partner or by an escrow service that could pick sides or screw both parties, whether on their own or threatened by a govt or other interested party.
So you’re saying add a fourth party (the government) and quadruple the cost (through compliance and taxes)? Sounds great! 😂