All I can go on is what people tell me. I actually only ask if the individual served in the military. Some just answer the question; others volunteer more details. I’ve been told flat feet (and other foot issues), poor eyesight, hearing problems, high blood pressure, too short, and so forth. Some of them were attempting to volunteer.
It may have made a difference who the doctors were making the determination and how closely or loosely they followed guidelines.
My enlistment was in 1966. I have no doubt that depending on the tactical situation in Vietnam at the time. When they needed more cannon fodder they would probably take one armed one eyed anybody anyway and anyhow.