I prefer to use cryptocurrency more than fiat because is faster, safer and with the recent spread of the deadly coronavirus you can be rest assured that the use of fiat currencies has several disadvantages. I can't use cryptocurrencies that much for any transaction because it's barely used in my country but i believe in the near future cryptocurrencies would take over the payment system.
Nah, both Crypto Currency and Paper money have their own advantages and disadvantages on one another and both are good to use in their own ways.In my country, Bitcoin and other forms of crypto are barely used also but the government does not prohibit its citizens to use Crypto Currencies as long as
they know what they are doing.
This one, both of them have its own strength and weaknesses.
Currently, we want to save more BTC in our wallets as an investment scheme. But for our daily lives people are still using it specially in third world countries wherein paperless transaction is not yet implemented by their government. So we just need to take the best of both worlds, take advantage of them. As far as the argument saying that banks will disappear because of crypto, I have doubts about that one.