There is also the two-mile run.
If two of your battle buddies were shot, which would you drag to safety first?
There are always stories of body builders that could not get hired by police departments because a table said they were overweight, but I never heard of that in the Army. Sure, we had a chart, but if you failed that, they taped you. I do not know how accurate that was, but it seemed adequate. I never heard complaints.
Let's say a skinny 5'0" Soldier made my life miserable and a 6'6" Captain America both get shot.
Weight is not everything.