Coach Walters really started from behind the 8-ball. Late choice of coach who had to make do with what was available, and for a first-time coach he did well. Blame O line problems and secondary problems on the last coach who left the cupboard bare having these problems when he was coach. Note how one of the better O linemen went into the transfer portal, he knew what to expect this year. Walter's tried to fix these problems with the best players available, he can't be faulted that no better players were out there that wanted to come to Purdue.
So he could have made some better choices during the game, but after all this was his first game as a head coach. When his recruits arrive in a few years things should get better. Hopefully adjustments can be made on both offense and defense to take care of some of the problems. It would have been nice to see them made during the game, for instance instead of seeing multiple plays made to score a few yard touchdown running the same ineffective play over and over again.
But what I find disturbing this season and last season is that when the team is ahead the offense quits playing and scoring unless the opponents score. It's amazing how then they can march down the length of the field and score, but then return to their complacency, be it the players and/or coaches. No wonder the defense gets tired.