I think the future of money, is a combination of bitcoin and fiat currency. Bitcoin will never replace fiat currency in the future because it is the material used in monetary system of country. All of the countries have their own fiat currency. It is more convenient to people if bitcoin will also be used as currency together with a fiat currency.
Cryptocurrency will be walking in our society only simultaneously with the national paper money of the states. It cannot be otherwise. Cryptocurrency is not able to replace the national money of the states. Today fiat currency is the simplest and most perfect system of monetary settlements. Our society for a long time will not be ready to switch to other payment systems. They will still exist in parallel with each other.
