This is not true, many countries do not intervene in the economy (are more liberal) and the real purpose of a Central Bank is to serve as a Bank for banks. They don't have to dictate monetary policy even if that's typical in many countries. A good example would be the role of a central bank in a country without a national currency.
Fractional Reserve is a banking system that allows commercial banks to make a profit by lending a portion of their customers' deposits, and only a portion of these deposits are stored in cash and available for withdrawal. Practically, the banking system makes money from nothing using a percentage of the bank's customer deposits.
But if you are in a country that does not recognize Crypto as a currency, what happens? Each country has a different policy regarding digital currencies. Moreover crypto currency is very volatile is not fixed. I think I will still need a bank, because not all countries of the world legalize digital currencies.