Banks will always be greedy and nothing will happen to them and as much as I feel you are saying all that out of bitterness to see banks go down completely, which I feel the same as well, unfortunately, it cannot happen. We all keep saying cryptocurrency is a threat, but with regulations, banks can start trading cryptocurrency as well and we may start having an over the counter transactions with banks, so at the end, they will still be able to play their card well to gain some relevance.
Presently, banks should not even see much threat yet since fiats will still always be needed until we get to a stage where cryptocurrencies can easily be used for day to day activities, but in that way regulation will still be the norm of the day anyway. Banks cannot collapse and even if the blockchain technology ends up taking over, they will still find a way to integrate it into the system to be able to stay relevant.
Can't really blame a system that was set up specifically to create the concept of money, and then create an economy revolving around their system... to want to maintain that system. But you're right. Despite all the things they've been blamed for, and all the things they have admitted to (how many global economic crisis have we had already? and debt crisis?), it's already so pervasive, so there's not much we can do to remove them even if we wanted to.
Banks long ago recognized crypto's decentralization as a threat. But they have won many battles now, brought regulations and centralization and even their own cryptos now. Their days are numbered, but will still be around for a very, very long time. We and our grandchildren will probably even still see them get stronger first before that.