Cryptocurrency is in many ways a natural evolution of prior representational systems, though one that favors truth over state-sanctioned power. He characterized digital currencies as just the 21st centurys version of that flimsy paper money and also pointed out that the decentralized and open character behind them stand in contrast to the government-run property systems (and the financial vehicles that followed it). According to Lubin, networked open platforms will eventually serve as the foundation for collective common-good relationships, overall replacing an adversarial system comprised of corporations and customers.
I don't see why not, there is no law that says that currencies only have to be the physical ones that you can hold in your hands, this is the new age and with new technological advances comes new ways to do things and cryptos is one of those new ways. They are just as much of a currency as any fiat currency and with time they will be the only accepted currencies