Agree with almost everything here El G, and well said. And yes, defensive ppg is how a D should be measured over the long haul. And it's easy to se why. Ya gotta score more points than ya give up.
As for taking the BPA in the draft, almost no team does it. And a lot depends on where a team stands as far as current talent. Can a team with no good answer at QB afford to not take a solid QB? Probably not, and really QB isn't the best example.
But that's not the Packers (they don't need a QB now anyway, although I would just say the jury is still out on whether Love was the BPA in 2020, my only disagreement). The Packers can afford to take the BPA, and if they were to do that over time, with discipline, they'd get better and have fewer busts. There are a few other practical limitations, but I like the idea of taking the BPA as a matter of practice.
I can easily argue with myself on this point. The Packers needs right now are LT, S, CB, and RB, roughly in order. If a solid LT is sitting there, I probably wouldn't be too upset if he was taken over a BPA. My point is that teams that consistently drafted the BPA would probably end up with better players. I'm certain I'll get disagreement on this. And it's pretty subjective anyway, especially after round 2 or 3.