Spending bitcoin should be more complex and worth it. You should not waste every amount of your bitcoin in your wallet and as soon as possible study the market. You should always keep in mind that good decision making is essential in bitcoin transactions and also in every market situation.
Banks are still a safe place for your fiat, although you have separate wallet from your bitcoin, you still need it. Bank accounts are still reliable for some other transactions where you need to refill your balance if you want to. It is better to have two wallets with a different type of currency so that you will not have a problem if you buy bitcoin on exchange.
Bank accounts are no longer necessary. No discrimination. 
No, even if you can legally spend bitcoin anywhere and anytime, you still need to have a bank account to refill balance your bitcoin balance in wallet. So far I have not found a way how someone can buy bitcoin on the exchange or a bitcoin atm without a bank account.Banks are still a safe place for your fiat, although you have separate wallet from your bitcoin, you still need it. Bank accounts are still reliable for some other transactions where you need to refill your balance if you want to. It is better to have two wallets with a different type of currency so that you will not have a problem if you buy bitcoin on exchange.