We're ultimately talking about combat, not the whole of the game, and we're talking about damage in to damage out and sustainability of such a model. That, at its core, is all combat boils down to.
I disagree with this statement about what combat boils down to. I find that to be, at best, an oversimplification of terms. However it is possibly even a gross miscatagorization of the factors at play in combat. Particularly when applied to the wide variety of what a mission objective may consist of.
I think it's fairly accurate to say combat always involves that and tends to revolve around that, but not to say that is all it boils down to.
Though I do agree that calling all factors of damage in and out dps is a hard mislabling. Also, I agree with the end point that the goal is not to stop people from thinking about the efficiency of it but to make that path varied ,mysterious or challenging.