This morden age one don't need holding a fist currency, we can save them as emergency funds and also invest in crypto currency if we want to become wealthy and successful in the future. Fiat currency lose value everyday and holding it will neither do one any good. Imo shitcoins and fiat are like one. Suggesting to invest in Bitcoin for the long term so can make a good profit within 2 circles of Bitcoin.
We don't really have a choice in that matter, do we? How will you buy groceries if you don't have any cash at all? Because, Bitcoin or cryptocurrencies are not accepted everywhere for now, so the fact that even if we want to hold no fiat, it's a compulsion for us to at least have some so that we can complete the daily basic financial requirements that we encounter until a time comes when cryptocurrencies might become the norm, but I really have doubts about that.
Whenever I think about a time when cryptocurrencies will be accepted everywhere, and we will stop using fiat currencies, but then I realize that the countries and their economies that exist on their currencies won't or can't let that happen. You will only be allowed to keep or use cryptocurrencies if you also keep fiat side-by-side because you won't be allowed to completely abandon it, systems will be designed that way.