If this will happen is it possible that decentralization be compromised?
I think its not going to happen! Since the two entities are on opposite sides, the one is for decentralizatio purpose while the other one is for centralized Banking purpose. But the Blockchain Technology is might be considered as a game changer to the Centralized Banking industry to reach the unbanked Population specially in the Third World countries, i hope it will realized in the soonest time possible!
I totally agree that cryptocurrency and bank wont unite but banking system are starting to accept blockchain and even some bank have started to get full details about how to implement blockchain technology to the banking system. If it gets success then i think most of the banks will start to accept blockchain. But dont relate both as same as bank wont accept crypto coins but they will accept blockchain technology.