There is a physical reality behind the magical screen of financial calculations. A large number of seniors will be a burden on a smaller number of workers no matter how you juggle the existing resources.
Yes, but to assume that government will accomplish this better than private markets is to truly live in Oz. Private investments will increase the GDP which will need to be divided up to provide benefits. Which increased GDP more, the money invested to create Microsoft or the identical amount spent on welfare, the military or a study of cow flatulence?