My opinion is that banks will live for a long time. Although they have an old system, but it is very well established and the guys from the banking system will not give up so simply a piece of the pie in favor of the technology of blockchain.
Yes that is true that banks will continue to survive for a long long time. I do not think that banks are going to quit so soon, because still majority of people are using banks for their main purposes. They are using bitcoin only as optional.
i think the bank is a government relationship and a financial support for a country, so i think conventional banks will still exist, and government will not leave it. even though bank system is changed to blockchain