I think you are trying to say the offense was not that great last year because it got more opportunities to score. It scored about 100 points more than the next best team, and opportunities matter little if the offense cannot put the ball in the endzone. The team also ranked
2nd all time in plays run in a season, which means the offense was capable of moving the chains and sustaining drives. It was about 600 yards off the record for yards gained by an offense in the season. If you are saying that is not impressive, then you must be frequently disappointed by the offensive performances with any OC.
And the fact the Pats were not as effective without Gronk is McDaniels's fault how? He didn't eliminate Hernandez, Welker, Lloyd, and Woodhead from the lineup. He planned for an offense that worked perfectly last year, and it was dismantled to be replaced by rookies. McDaniels cannot eliminate drops, and he cannot transform rookie wideouts into Gronkowski. Nor can he magically heal Gronkowski and get him back on the field. If you believe a 'good' OC can do any of those things, then you need to read more on the great OCs of the past because you simply don't understand the job of the OC.
Everybody in the media dumped on Brady early this year, when anyone with a clue could see it was personnel changes. As the personnel grew into the system, Brady looked more like Brady. He is the GOAT, but he cannot throw and catch the ball himself. He cannot stop Ridley from fumbling. Neither can McDaniels.