All of this is arguments about the correct measure of DPR. I don't see how you're not viewing the issue through a "DPR lens". You're arguing that a proper measure of DPR requires having regard to a wider range of elements in the tactical situation.Look at the post I quoted. He's basically saying that most people are going to take a greatsword because it does more damage, which is viewing the issue through a DPR lens. And an individual one at that. It's more about "how can I as an individual optimize my DPR" and less about team effectiveness, which is probably how most DPR analysis goes. It also only looks at the issue through a white room analysis, as he's comparing polearm damage vs greatsword damage straight across, and doesn't even consider how often the advantages of using a polearm over a greatsword can come up in actual play. Even without feats, the advantages of formation fighting are pretty significant, and have been a common tactic since the first days of D&D
It's not really any different from discussions about wizard DPR where one person fails to factor in the AoE, multi-target component of many wizard attacks. Or discussions about DPR vs goblins and kobolds which don't have regard to the pointlessness of excess damage.
TL;DR - you don't step out of a "DPR mindset" by arguing that someone miscalculated DPR.