digital money sooner or later will replace paper bills, in the age of information technology, there is a huge number of applications PayPal, samsung pay and many others that are very convenient to use and the phone is always at hand
I think even if they are becoming popular we cannot still replace fiat currencies and its worth and how it can be use everywhere even without electricity, gadgets and internet connections.
Digital currency also comes from fiat currency dude lol, digital currency is another form of fiat. in many countries nowadays digital currency has been widely used, we have often seen people shopping using credit cards or even mobile banking, it is a form of cashless society and that is definitely will happen sooner or later, but for everyone to use it will certainly take a long time