There was nothing special about Northwestern’s offense in 2020. In fact, by most metrics and raw statistics it was well below average.
Bill Connelly’s S&P+ ratings (widely accepted as the best one-number metric in college football) ranked Northwestern’s offense a mere 93rd out of 127 FBS teams at the end of the season. It doesn’t help that S&P+ factors in the performance of previous years for consistency, as the 2019 Northwestern offense was an all-time deadweight anchor dragging the 2020 ‘Cats to the bottom as much as humanly possible.
Either way, it’s pretty clear that NU once again succeeded because of their defense last year, and while it certainly wasn’t in spite of the offense, one side of the ball clearly superseded the other.