are you referring to digital currency such as bitcoin or digital fiat currency? as paper money could be used in form of digital since people have been using it seamlessly integrated into the payment methods. No need to convince people to use bitcoin, it meant to be an alternative, not to replace current fiat currency, unless the country broke then bitcoin is a good option for the citizens, although the developers still have to make sure to resolve scalability problem to perform as convenient as fiat currency.