Put things in context:
I put you up against a wall where you can't move.
I allow that 4,000-lb Suburban to impact you doing 1 ft/sec
I submit the area of your gut so impacted is tantamount to mush
approx 1 sec later.
It's all in how you set up the problem.
I'll admit that terminal ballistics/performance is incredibly complex, and greatly
not only on bullet speed/diameter/weight, but also on bullet metplat (at BP and/or non-exotic
handgun speeds), sectional density, jacket design (high speeds), target characteristics (skin
types/flesh/organ densities/voids, bones/thicknesses, impact angles, intervening
glass/metal/wood barriers, etc, etc, etc
But energy does
finally matter -- within those contexts