Even without computers we can use crypto if we have smartphones but we can't use it if there's no internet.
We can't fully eliminate fiats, this is the truth for now because of the modern technologies that are emerging.
People can't decide on what they can trust and use but for us crypto rocks!
it is very true that your opinion of removing fiat currency is very difficult, maybe one day fiat and cryptocurrencies can go hand in hand and be mutually beneficial because we also know the legality problem with cryptocurrencies, many countries that oppose cryptocurrencies become the prevailing currency in the economy of their country