It is solid only if it were true. Alas it is not. The young will be getting into the business of subsidizing the old, above and beyond medicare. They are being asked to overpay for their insurance. The moral hazard was the nose in the tent, to move them from free riders into subsidizers - from one end of the field to the other. And we still have a dysfunctional delivery system, with not much competition and price policing to boot.
And when I'm old, the young will pay for me. And when they're old, the new young will pay for them. It's the fairest way to do it.