Nor have they explained how we are going to a handle a situation where ~5-20% of the under-65 people who will catch it all at once will require hospitalization.
Hospitals in affected areas are currently overwhelmed, with people under 65 alone. Italy has stopped treating people under 60. And this is when the vast majority of people under-65 are not infected!
Somehow, I doubt their situation would improve if people over 65 stopped getting sick, while people under 65 started getting sick at 4x or 5x the rate.