Exactly. To blame that season on the offense is a little bit ignorant. TT and WV were 100% on the defense. Baylor was more special teams than anything. I'll blame the offense for the losses to iowa and Clemson. OU we just got outclassed.
I'm not going to say that Manning was a great OC. But, when you have a bad OL and no real deep threats at WR, there's not a lot he can do as far as play calling. Then this year you add RB injuries and the running game goes to crap. I put the blame more on OL evaluation, development and scheme than anything. Now Manning has something to do with that as well, but he kind of shares the blame with Campbell and Meyers there.
Manning had some of the best ever offenses at ISU. They successfully transitioned from a deep game with Lazard and Butler to a short passing game with Kolar, Allen and X. Good OCs run schemes based on the talent at hand and he did that. That said, the Toledo OL system obviously was not working and they probably should have moved on from Meyers a year earlier. I think that Manning was a little bit of a scapegoat, but there was plenty of blame to go around for both 21 and 22. He deserved a portion of it, but not all of it.