It is very clear that technology is on the rise [and cryptocurrency is surely a big part of that technology], but for those people who were living in extreme poverty, cryptocurrency is anything but just one plain simple word and mean nothing at all. Those people living in rural areas [far away provinces with still no electricity], i believe, fiat is the only currency they were familiar with and will accept.
Despite the given fact above, for some who were given the opportunity to be knowledgeable about and earned a lot from cryptocurrencies, there is no doubt that this will be their preferred one. With reasons like; no middleman, trustless design, secure, etc.
Cryptocurrency is very much still volatile that's why, i, personally, still prefer fiat than cryptocurrency. In addition, we still need fiat to buy those cryptocurrencies in the first place right?