Isn't the "gold standard" the same as other primitive currencies like puka shells or shiny beads?

What you point out is pretty much true. Some currencies are, or were, based of things other than gold. One island used huge stone "coins" as their currency base. Some people used fur or livestock as their wealth. It all boils down to an agreement that something is worth a given amount. As far is going back to a gold standard, all people have their blind spots and biases. It doesn't matter if their smart or not. The gold standard would not be viable for many of the top industrial nations today. The price of gold would have to be locked into the currency. If the price of gold went up the currency would be worth more. If it went down the currency would be worth less. This could lead to major gold smuggling as people tried to get more for their gold.