The people behind the banks have played really well and they have made the banking industry key to keep the current status quo, so governments regardless of whether they want or not will have to keep rescuing them despite the protests of their citizens, so banks have no incentive at all to be responsible when they can be rescued at any time and for any reason, so it is unlikely that decentralization will take over the world even if banks were to collapse.
I don't even think so. All of money were coming from the centralized parties. The decentralization will not have value if there would be no money came from centralized parties. You received your payment and you withdraw it to your bank account and then cash out it to pay bell in your real life. A few bank collapse is not comparable with so many exchange sites in the crypto that goes bankrupt and scam.