i do not think so that bank can disappear by bitcoin , hope that they will work in cooperation with each other, and bank will accept bitocin for deposit and withdraw.
it is an interesting collaboration. maybe even someday Bitcoin can be stored in a conventional BANK. it is one thing that must be realized. BANK's financial system and bitcoin will increase.
Take note that it is not only USD that the banks store but every other popular currencies as well.
We may as well hope for bitcoin to be integrated in the banks. That would be awesome and beautiful and helpful.