No I do not think that banks can be destroyed by the bitcoin itself, the government will indeed stop this and the banks itself also has enough power to stop this easily.
I don't assume so, bitcoin can't destroy banks and the other way around is true too. As bitcoin's existence doesn't have anything to deal with banks' ones, bitcoin is cryptocurrency, which is new technology, and throughout the time, it has claimed its position in the economic world, while banks represent for fiat money, which is one of the first things that appeared in the world development and still plays an important role in our life, these two things can't eliminate each other.