Sheltering in place for months or even a year is not going to weaken your immune system. You do not need to panic about your precious immune system so much. Rest easy knowing you’ve been exposed to enough germs over the years, and use some common sense. Being clean for a few weeks or months is not going to kill you!
So you are saying the way to combat the virus is natural selection, rather than science, medicine, and social policy? Let the weak die, so in 5 years the remaining strong people won’t have to worry about any pesky virus? Until Covid-24 comes along, and we’ll have to sacrifice another chunk of the population to natural selection, to improve the collective health of mankind’s immune system?
Are you trying to calculate the Covid-19 CFR for Sweden? Do you realize you have only calculated the % of Swedes to die from the virus? They did not all catch the virus and their government did encourage voluntary social distancing, which has been very popular. Their # of dead is just their # of dead so far, and likely only a small % of their population has contracted the virus thanks to their popular voluntary social distancing efforts (although not as effective as mandatory policies in neighboring countries).
“I have gone through many seasonal influenza sagas with higher death rates, unfortunately.” So you were around in 1918?