What are the chances of living in a world with no actual money ?
I think personally that cryptocurrencies won’t make FIAT useless, but I think that cryptocurrencies will work hand-in-hand with FIAT money.
I think there are two issues here
a) if you are asking if cryptos will become the only kind of money: no, as long as cryptos are not declared legal tenders.
In every country there must be a legal tender, a currency which sellers are obligated to accept.
It's possible that Gov or Central Bank will create some kind of cryptocurrency and declare it legal tender.
b) Fiat is money created ex nihilo by the central banks. Fiat is fake money.
The proof of it is what we call inflation. Currency depreciation.
Fiat, this kind of money exists only since the 70ies, when the USA withdrew unilaterally from the international agreements of Bretton Woods.
Before that money was gold, the Gold Standard.
Cryptos won't make money useless, they will make fiat useless.