As you say, most women are considerably smaller than most men. Small men are at a disadvantage in combat, though it never seemed to slow the Japs or VC down all that much.
So here she is, probably 40% less strength than a shrimpy man of equal size, and she’s surprised that she didn’t pass.
BTW, that bit where she just collapsed and couldn’t go on? What does she think happens in combat to someone taken that way? Either somebody takes care of her, drastically reducing the unit’s efficiency, or she dies.
I’ve got an idea...let’s take all the women who want to be in combat and put them on the BLM SWAT team. The next stand-off can reveal 4-5 gals who are 5’3” tall trying to take down an old, 6’ rancher...