This could happen one day when banks can no longer compete with Bitcoin because everyone uses it like they currently use fiat money. But as long as fiat money remains trusted by all governments around the world, it will continue to be used by everyone, even if everyone loves Bitcoin as much as they love money. Banks could take advantage of this opportunity to earn fees when people buy or exchange Bitcoin through their services. However, I still prefer to stick with certain exchanges if I only want to exchange Bitcoin for other assets like fiat money.
The financial system that has been built by a country cannot be changed quickly, and banks are affiliated with government regulations along the way.
In the future, this may happen because nothing is impossible in this world, but it will take time because it cannot be forced to be implemented faster.
Regarding the issue of fiat currency still being used by all countries, that is another matter, and perhaps the discussion lies in the acceptance and policies of banks in evolving to accept Bitcoin deposits.
If this opportunity is seized, banks can profitably charge service fees, ultimately benefiting the country. But essentially, we already have our own bank in our wallet, which allows for greater transparency and ease of operation.