Its hard to say what is gonna happen with it if this happen but I think that we can not say it will disappear because the most of us will most likely stay using is it because you can do it a sort of anonymously right ?
That would still be a problem. The people or establishments that will accept it will be lessened and how are we suppose to use it with that?
We think of it as money and because we buy it also before investing it. What good will it help us if it doesnt have any value.