Defense wins championships is more than a platitude.
Look at how many shutouts the 55-56 sooners had under Wilkinson.
Billy Tubbs was a great offensive coach, but pretty darn good on defense, but not the stall, slow style. He wanted chances for turnovers, or force the opposition into quick shots.
ALL good coaches emphasize defense as well as offense. Just because fans enjoy offense and scoring, You WILL NOT win consistently if you play bad defense, and you can often win with great defense, and so-so offense.
And old does not mean passe. At least I hope not as I sure fit the old part.
Submitted as my opinion only, I am not in total disagreement with what you say. You can't be one dimensional and win, with either offense of defense. You may be better at one than the other, but you have to be adequate or better at both.