“I’m talking about using the money we used in the past, which contained gold & silver. When you cross a border, the person on the other side doesn’t care whose face is on the money, or what language - they only care about the content.”
The problem is that today people can in fact fake that gold so good that only a expert with lots of expensive equipment can tell the fakes from real gold coins.
True, but the same problem persists with paper money. When the US changed the $100 years ago, I was in another country a couple of months later and they already wouldn’t accept them - too many fakes.
I don’t have all the answers, but I’d rather have the metal than a piece of paper.