Energy without suitable bullet performance is like horsepower without traction. Lots of potential, no work getting done. If no or little work is getting done then maybe energy could be viewed as an empty number. Or maybe you're just a shopping trip away from hooking that energy up and really having something.
On the other hand, the fanciest, most expensive,carefully selected, most highly promoted bullet can't do anything without energy. No matter what design efforts are made to optimize damage, sooner or later you reach a point where no further improvements are possible. You can't get something that isn't there. To keep up with the analogy, all the traction in the world wont do anything without energy. No energy, no work. No transfer, no work.
You have to have both. One's no good without the other. To argue that energy doesn't matter just means you're spinning your figurative wheels. And maybe your literal ones as well.
