The European Parliaments Committee on Economic and Monetary Affairs (ECON) has come up with a report on cryptocurrency entitled Virtual currencies and central banks monetary policy: challenges ahead. The finding of reports shows that cryptocurrency will not replace fiat currency, even in the long term.
https://bit.ly/2NeLgLrI also think the same way but only for all existing cryptocurrency that is not issued by any government cannot replace fiat, while I think that there are chances that fiat currency can be replaced by a cryptocurrency made by the government but should more likely work as an alternative. The reason why cryptocurrencies like Bitcoin might not have a chance to replace fiat is because of decentralization and the highly volatile price, and we all know that governments wants to control everything especially when it comes to money. Btw why is the link of your source should be shortened? lol