I appreciate the article.
I think your argument I find most dubious is the idea that we have lessened health care capacity by sheltering at place and closing businesses. Even if we have furloughed hospital workers, and I'm not saying that isn't a huge blow to those people and their livelihoods, and stopped elective surgeries, and I'm also not saying that those elective surgeries aren't things that don't matter, I think in terms of the next 6 months, the chance that our hospitals have less capacity to deal with serious illnesses that lead to death seem unlikely. If anything the decrease in deaths from other things, like drunk driving, and influenza might offset the loss in capacity from those furloughed.
I agree that if the timeframe is long enough it is very likely to ultimately lead to more deaths from missing elective surgeries and preventative healthcare, and I think the argument for Pareto-efficiency and only asking those who are at risk to shelter in place isn't dismissed with this argument, but I don't think a time frame of say 6 months to a year would lead to more deaths in the way you state. I think you should maybe specify (or point out to me where you state this if I missed it, i'm not a careful reader) what kind of timeframe you believe that the combination of lack of capacity and missing out on preventive measures would start to lead to more deaths and indicate where you think we would reach pareto efficiency. Have we already passed the point of pareto efficiency? Was it never good at all, and the most efficient thing to do was no response?
I personally think you wouldn't see the effects you are talking about for probably at least a year, and I'm hoping it doesn't last that long. I think you might start to see an increase in deaths from other things like, overdose, alcohol, and suicide, in a shorter timeframe than that though, and that is something that probably should be weighed in picking the best time to end the lockdown too.