Yeah, all of the newly publicly acknowledged technologies and economic models can be applied to most aspects of our life. This mean that bank can use them, But, However, for large enormous banks to change their entire system and for the security of their huge transactions as they would be published on Blochchain to be ensured, it wouldn't be an easy task. And also, such banks would need huge networks of miners, which are temporary inadequate and would still be hard to build in the future.