The offense was 24th in yards and 26th in points last year. They've lost their only legit receiver. Mooney is a #3 on most teams and a #2 at best in a mediocre offense. Struggling line, no receivers, unproven QB, and new offensive system with a coordinator who's never called plays before.
What in the world makes you think the offense will be average? They'll be a bottom 5 offense if not the absolute worst.
You forgot to mention that their best receiver had a really bad year so him being gone is not some huge loss.
And you also failed to mention the biggest positive for the offense going into 2022.
No Nagy!
Replacing Nagy with a bag of smelly underwear would move the offense up at least 5 spots. Replacing Nagy with a potentially good OC moves them into the top half of the league on offense.
Sure, there will be growing pains as the year goes along, but the Bears were never going to be a Super Bowl contender in 2022.
If the defense drops a bit and falls to a top 15 defense and the offense can get to the low 20s, it will be a major step forward during a "redecorating" year.
2023 will allow the Bears to add some missing pieces from 2022, making them a more complete team.