Of course it would still be necessary in the world. From the first place, for how many decades, we are using fiats for day to day transactions. You cannot eliminate that right away even though the possibilities of crypto in economy is high. There are benefits of crypto and the same with fiat. We can use both of them for our everyday life.
Right.Fiat currencies are still very beneficial to the majority of the people nowadays since they are still using it to buy their goods and pay for services.Maybe in the future it will be less necessary when most of the people are exposed already in using cryptocurrencies.I think it will only happen once the government decides to accept cryptos and legalized its usage.