On the flip side of your first two points, you see the immediate impact firing him had on the Packers after missing the postseason in 2017 and 2018, and they went after Matt LaFleur who had only a couple of years of OC experience. He was ND's QB coach in 2014 for crying out loud. He got them to the NFC Championship his first two seasons and revitalized an aging Rodgers to the tune of back-to-back MVPs running a much different offense.
McCarthy is a solid dude, a good coach...but the League has passed him up, IMO. I'm shocked, I thought that having Bill Belichick available would have been enough for Jones to take a swing at the coaching carousel.