The role of banks is difficult to be eliminated although the use of cryptocurrency continues to increase, I'm sure that if bitcoin has defeated the banks then the role of banks will increase and soon receive bitcoin.
Even in the age of crypto currencies one thing I am very confident about is that Banks are never ever going to lose its importance in the modern world. Banks are very much essential for the economy of every country and there its important for the global economy as well because when you invest into cryptos you are going to eventually cash out.