Don’t forget India and its government’s push towards a cashless system. You are operating on a false assumption – the assumption that the way things are now and the social mindset surrounding them will always be the same. Public mindsets change quickly with crisis. Initiate a crisis in the dollar, for example, by destroying its reserve status, and you have suddenly added quite a lot of inspiration for the American public to adopt a new system. Perhaps even a cashless one.
Never make the argument that a specific economic shift of one kind or another is not possible or unlikely. Yes, it may take “years”, but not as long as the naysayers believe in the event of a fiscal catastrophe. Consider that precious metals were the defacto currency system for thousands of years, and tied to paper currencies for decades. Yet, in relatively short span of time during and after WWII and the Depression, gold was buried and fiat became the ruler of the monetary world.