Have you ever considered that the defense may not be intentionally faulty? Like what if Capers has never said "The goal is to give up 30 points this week" or "We're just not going to try controlling the line of scrimmage"? What if Thompson has never said "Lets pass on that guy, he's too physical for us"?

What if there are 31 other teams also trying to build the perfect defense and competing for all the same resources and even the most fortunate one still won't give up just 13 points per game?

And to answer your question yes there are other teams just as QB dependent. The Broncos, Bears, Giants, Steelers, Saints, and Patriots all come to mind. I'd wager nearly every team would also be smoldering heap of dysfunction after losing 20 million dollars worth of their best players.