Monometalism is a modern statist creation.
Discussion
OK sure, but that doesn't change the fact that bitcoin is a better method of exchange than any physical metal coin. Gold or otherwise.
I can weigh metal coins but I have no way to verify on the spot it's not a forgery.
I have to carry around coins and someone has to have a scale.
These old methods worked in a historical context and will continue to work in a post apocalyptic type of context. But in today's current society, bitcoin is better.