Even if people don't turn bitcoin into an investment, a store of value and use it for its original purpose. That doesn't change the fact that it won't replace banks. Because a bank is a large financial institution that is run and managed by thousands of people to be able to operate smoothly and provide many services to the economy. Meanwhile, bitcoin is just a currency like fiat or a store of value like gold, all of them are just tools. How can it compare and replace the role of banks?
Bitcoin has its own goals and use cases, it's not created to replace the traditional banking system. Banks are part of every central government's that gives them authority to control the financial system of the country. So far no central government has surrendered its financial authority to bitcoin. The countries that have adopted Bitcoin have in actual regulated its use in the country and that regulation has given the central government control over the Bitcoin. For me Bitcoin will continue to exist beside central banks and fiat currency.