Bitcoin can make banks disappear, but only with permission from the banks, because their stay is determined by those banks. Think about what I am saying, it is true. I have talked to alot of banks and they gave me this impression.
Banks can't do much without guidance from the government, and thus it's not the banks, but the governments that have the final bit of saying here. Banks don't only serve as an easy way of transacting, storing money, taking loans, etc, but also as a tool for governments to determine who owns what amount. It's not in the governments benefit to replace or change the current banking structure. But that's also not something we as Bitcoiners should be focusing at as it's quite pointless.