This was my graph, so I modified it...anyone who has ever had a jacket or boots issued to them in situations where supply levels are less than optimal knows the truth of the statement: The military operates on averages.
A military planner doesn't design a task that only 20% of males between the ages of 18 and 45 can do, they design it so that everyone in that MOS can perform it, and then they make sure people are up to the task.
For example, they know that if they make a 15 mile march with 80 lb packs, guys who get into that specific specialty that needs to do those marches will have the physical capability to do it. They also know that if they make it a 25 mile march with 80 lb packs, the percentage of men who can be counted on to complete it is going to drop.
If you are in an artillery unit, they probably figure a man can walk one 105 mm shell twenty yards in one minute and perform that task repeatedly over some interval of time. (I am making up all of this, I don't know the demands or requirements, just using these as examples.)
So they try not to make things impossible...for the greatest number of soldiers, sailors, or Marines.
You also need to color the area to the right of the left blue line that is under the green dotted curve, but above the black dotted curve.
When you do, approximately 40% of women are capable of the minimum required of men.
This is not meant as a criticism or disrespect of women. I know women can mentally be smart and tough. It is a statement of fact that no amount of Hollywood or feminist indoctrination will be able to change.
That may be the cases in training scenarios. Actual war is different.
In actual war, the side which has the most people able to do the most difficult challenges, is more likely to win. The side which is unable to match or beat their opponents' capabilities, will die.