People with lack of knowledge will never know what bitcoin is all about and what are its benefits, and the fact is people resist change, and they will never get into bitcoins.
I will just take some time for the ordinary people to use the bitcoin. If major banks are involved, it is not too difficult.
They will be as soon as they they see how it will profit them in the future then they will start adapting it. Problem is eyes are still closed in to newer things that might involved some risks. They just want to stay to that kind of way where they know there will be no risk.