2.If you imagine in let's say 20 years FIAT goes to CRYPTO all the way. You want to buy a car worth $5000 but paying in Crypto, how much would you pay ? if $ got no value.
This is not gonna happen, bitcoin is a good payment system but we have to understand that it will still remain as an alternative, fiat will never replace by anything that is out of control by the government especially bitcoin is even a decentralized form of money.