Both for now. In future depends from situation, I think we need both now. Some things I can do with bank I cant do with btc and opposite. I would like to use just bitcoins for everything but who knows when will that be possible. Not in some near future for sure.
I dont think bank wish to solve anything, they are using this mess to make more and more profit for them. They will try to do something with blockchain tech. this is future, will they go with btc or some other (maybe they will make new one) is yet to be seen, but I bet they will do something I`m curious to see what.