It’s called “Stratify and Shield” and it’s far more compatible with a free culture than house arrest which is the current strategy. If young people decide to expose themselves to the virus then some will be infected and eventually the culture will develop the “Herd Immuity” that marks the end of the pandemic. Meanwhile those over 70 can be ORDERED TO STAY AT HOME… House Arrest if you will, to protect the most vulnerable in the culture. A paper was presented that covers this idea HERE. but don’t run with the idea without further study and evaluation..