Banks will adapt to Bitcoin as well. Exchanges currently scoop up so much in fee income, that the largest exchanges generate more profits than some large legacy banks, which is something they for sure want a piece of.

Banks have the best possible chances to accomplish that with how they can allow people to instantly buy crypto out of their own pool of resources, while with exchanges people have to wire money first, which takes days.

No way banks aren't already in the background working on this. They are businesses out to increase their revenue and profits, and what else than the booming crypto market will allow them to capture that exposure?