What needs to happen is to reduce the connectedness of the human social graph. The elderly don't need to be totally isolated. They can be seen by family, friends, but we need to limit the number of people that each older person can see, and the number of people that are seen by each younger person. That's what this social distancing is about. The virus travels along nodes where our paths through spacetime intersect or come close, and that is in many cases closely modeled by the human social graph. If you reduce the connectedness of the graph, you reduce the number of potential intersections each carrier has with uninfected people. You do that enough, and you can get the reproduction rate below 1. You do that enough and we can catch up to the infection front and seal it off.

At least, that's the hope as I understand it. That's what I'm trying to help do by staying home and seeing only close friends and only in 1:1 settings.