This is in a ways an apples to oranges comparison. Arrows are designed to kill by massive hemorrhage and thus it is imperative that they are sharp enough to avoid vascular constriction at impact due to shock. That's why cut on impact broadheads are always preached, especially with slower traditional bows. I've seen a moose take a direct heart shot with an arrow...he flinched slightly, looked around and continued eating. About 15 seconds he literally just fell over. Sharp arrow and proper shot placement = quick humane kill.Velocity and mass do trump. Along with expansion of the bullet. Put them into a calculator. Blk round produces 441ft/lbs of kinetic energy. The bow produces 44ft/lbs. If it wasn’t a factor then why do the hearts look like jello when shot rather than just have a hole in them.
Bullets kill partly due to hemorrhage but mostly due to the shock of the bullet disrupting organ function, or a combination of the two. Subsonic bullets are inducing enough shock to cause vascular constriction and delaying massive blood loss, but not enough to cause a disruption to organ function like a supersonic bullet would and are really borderline unethical for hunting any kind of big game in my opinion. But again that's just my opinion.