Banks wont go anyway further the place they are right now, bitcoin has no skills to make loans for a long period, neither be able to allow to earn 1-3% monthly, even knowing bitcoin its very volatil. I do understand that bitcoin bank might allow people to earn those interest, but the thing is it will put several bitcoins into one place, and hackers will try to get acess to them, they already crossed the walls from banks more then once, soo i would avoid it.