I don't have any reasons not to trust banks because as far as I know, banking storage of money is reliable and many business owners deposited their assets on a savings accounts they have for fiat cash money. Well if we ignore trusting banks its not worth earning btc because we can use fiat cash money, to exchange it from digital currency to fiat currency by using online wallet which has an option for bank cash-out.
I think there is no reason for us not to believe the bank while we were depending on the bank. no need hypocritical not to use banks. because I'm sure you also use the help of the bank to convert bitcoin to fiat
With no ability to turn BTC into fiat, Bitcoin would never reach such price and attention level. Sure, it's possible to sell coins outside banking system, but it's rather marginal part of world's market volume. We are praising BTC as a standalone mean of payment, but actually almost every single BTC would be transferred in to market one day, and will be sold to someone else for fiat.
No. People still know how to use Bitcoin without converting it into dollar. When bitcoin was created, hackers still use Bitcoin for many illegal activities without changing it into FIAT. Then, people recognized the benefits of bitcoin and start buying it and hold it as a type of investment. Keep in mind that Bitcoin can still survive no matter how the world change, while Fiat can be destroyed by physical damage