I get the sentiment, but I can't agree they would be that bad.
My reasoning is that we have only seen Mitch here in Buffalo late in games when they are running the clock out and in preseason where they are just running basic plays.
I have some faith that if we knew Josh was missing the season that Joe Brady can scheme up an offense that goes more to the things Mitch does well.
It really wasn't that long ago Trubisky was the QB of not one but two not so good Bears teams that made the playoffs...with Matt Nagy as HC.
So IMO, either Mitch is a bit better than we are thinking, or the NFL has severely overlooked Matt Nagy as a legitimate amazing head coaching candidate for a second chance.