This doesn’t make much sense because life expectancy cohorts are grouped by the year they are born, not the year they died. The concept of a “strong” vs “weak”

This doesn’t make much sense because life expectancy cohorts are grouped by the year they are born, not the year they died. The concept of a “strong” vs “weak” immune system also doesn’t correspond to reality: for the flu, it’s hypothesized that it’s too strong an immune reaction that kills you. Many of today’s leading causes of death also don’t have much to do with the immune system, from the opioid epidemic to heart attacks, strokes, and cancer. Autoimmune disease is far ahead as a public health issue compared to infectious disease, from MS to (probably) vascular disease (edit: see this other story currently on the front page https://news.ycombinator.com/item?id=19742188 https://news.ycombinator.com/item?id=19742188)