You don’t “need” to spend the resources to give value to the metals…..the work / cost of making them into coins was a sort cost of “insurance / simplifier” that made them more “reliable”…..the coins were more “difficult” to replicate (so less likely to be fake material) and as coins that them more reliably reflect a specific weight (value) of metal……so to me the coining was not required except to make use easier and more reliable.
You could very well offered up to everyone a small chemistry set for material purity testing and an accurate triple beam balance…..but I suspect that no have done the job quite as well.
I might have to read his reasons just for kicks…..he is the type of guy who has been seen crushing high school drop-outs in debates.