I fail to see relevancy here. If a physical good is made illegal to own and trade most people can not do anything about it. You'd have to smuggle the goods out of the country or find someone who is willing to take that risk. Most people simply do not have resources to do this.

With digital goods such restrictions aren't nearly as big of an issue. You can trade (semi-)anonymously with very little fear of getting caught. You can easily disguise your country of origin and even hold the money off shore, all of which would have required a lot of capital to setup with actual gold in the 1930s.