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.
Banks have the power to do whatever they want. After all, they're patronized by mainstream governments. If all else fails, banks can easily hit "the reset button", to drive the economy to their own favor. It's manipulation/corruption at its finest. With Bitcoin, it's another story. There's no central authority behind it, becoming impossible to change its supply at will. It's one of the many things that makes Bitcoin better than Fiat.
I think BTC and other cryptocurrencies are set for a rally as central banks increase their balance sheets to prevent another collapse. People are starting to distrust these powerful entities, so it should only be a matter of time before crypto/Blockchain tech (especially Bitcoin) takes over the world. Who knows if early adopters like us will become extremely lucky in the future? Just my opinion

Without a doubt bitcoin is better than fiat, however those at the very top benefit from having such an unfair system in which they can abuse money printing and their political power to do whatever they want, and it is unlikely they are going to be persuaded to change their ways, so they see in bitcoin an enemy that must be destroyed or at least tamed so it does not become a threat to them, this is why we are seeing so many regulations against this market lately, as those powerful people are worried they have pushed the economy too much and people begin to adopt bitcoin as a way to protect themselves from their manipulation.