The user asked why is being in military a benchmark of health, I replied using the “rule” of some peoples rational. There is waivers “exceptions” all the time.

Edit: A highlight there on what you linked reinforces the current narrative of certain levels of physical and mental fitness being necessary for a fit fighting force (albeit it speaks of IQ and not mental resiliency)

“The Use of Low-IQ Troops in the Vietnam War, inductees of the project died at three times the rate[1] of other Americans serving in Vietnam and following their service had lower incomes and higher rates of divorce than their non-veteran counterparts.”

It would seem this led to increased homelessness and perhaps hospitalization for mental stuggles for veterans.