Banking will surely take advantage of the blockchain technology. In fact, many banks have already started to take advantage of the blockchain. One such example would be Barclays which be using it for ned users and completely integrate into their system.
Also, you should have heard about Ripple. It is surely a centralized solution but enables banks to do cross-platform payments more quickly and securely.
Check this article out on how
Ripple wants XRP to be Bitcoin for banks.Also, you might have heard about private blockchains. They are not similar to banks, but not completely. You can read more about the difference in a
detailed article by Swati on 101blockchain.Overall, I think Banks have to adapt blockchain. Also, there are plenty of reasons to like blockchain,
but not Bitcoin.