I heard a pretty smart epidemiologist make the argument that herd immunity may be the answer. With a death rate below 60, of somewhere around 1 in a 10000, the risk to this population segment is not markedly increased by emerging.
Given that this constitutes some 85% of the population...who once exposed and immune would constitute no risk to the other vulnerable 15%....it probably sets up enough dead ends for the virus to die out.
This could all happen fairly quickly given how infectious the virus is. Perhaps quickly enough to prevent a second wave.
The theory of shelter in place assumes a wave 2 is inevitable and the really vulnerable are best protected by protecting everyone. It was also predicated on the risk of overwhelming the hospitals.
But hospitals are getting less patients than predicted and are increasingly on top of things. So if the vaccine is as uncertain as it seems, it’s worth asking the question whether going for herd immunity isn’t the wiser course.