Fiat-currency issued by central-bank/government has its solid physical form whereas the cryptocurrency does not. However, the mechanism of how this cryptocurrency works is closer to the original concept of currency
These cryptocurrencies cannot be excessively printed more than the market demands for the sake of the monopolistic organisation such as central-banks, governments, and big corporations aided by them.
The problem of cryptocurrency is that it requires the technology and the mining capacity of computers across the world to back up with. It is still not convenient for everyone enough to frequently use in our daily life yet.