Exactly right, Jessica.
That Lostallhope chart is bandied around as though it represents the findings of a scientific survey, often by people from whom you might expect a more critical evaluation.
Same goes for much of the stuff on this forum.
Soldiers and police are trained to fire at the centre of the target to optimise the chances of a hit. For a standing crouching man this is the lower chest/solar plexus area. Incapacitating the target is what is required, not necessarily instant death. Indeed, in military terms, a badly wounded enemy is a better result than a dead one.
Military snipers and police precision riflemen (same thing) may be called upon to kill instantly in some circumstances, and then they shoot at the head on a level with the mouth which usually results in the medulla being hit.