If I remember right we have been historically a man D. Something changed. My guess is that coaches thought the young guys cannot perform in man. It was probably seen in practice. Coaches see the players longer in practice than we do and decided to go zone and rely on pressure. Yes that means giving up some yards in the hope that the game is not lost because of it. I guess that's a bend but don't break mentality or even the dreaded prevent defense.
But it can work if pass rush pressure does what it is supposed to. And sometimes its just players not plays and our players are not doing their jobs for whatever reason.