There is a huge competition between cryptocurrencies, many believe just dynamic and self fulfilling ideas with different properties and a variety of incentives may survive! Others expect fiat money will leave behind reliance on quantitative competition!
I think cryptocurrencies are not able to defeat fiat currencies without changing nations culture and ethics! what do you think?
In my opinion, in the next 5 or 10 years, crypto can't change fiat, but if it's 20 years or more, it's possible that cryptyo will compete with fiat, maybe transactions will use digital currency. that's my prediction.