Cryptocurrency is the future of all payment method due to the decentralized nature which grants financial freedom and power to the people. However, for it to replace cash or the Fiat, it will take years of awareness creation. Up to date, some people do not have access to internet whereas others do not know how to access it.
for the near future I don't think that is possible, because after all each country has fiat currency protected by law. maybe we will need more than a decade to make this happen, but it is likely that it needs major changes, a kind of revolution for example.
