Yeah?
Well, MM is ranked 6th among all active HC's in winning percentage. That is significantly more meaningful to me.
He's ranked 5th in wins with 155. That is meaningful because it meant that he kept his jobs long enough to win that many games. That leads me to conclude that he is pretty good at what he does.
MM is one of only 8 active HC's to win a Super Bowl. Twelve of the guys ranked ahead of him have not yet achieved what they are hired to do. They have not won a Super Bowl. If they eventually win, then they get to keep their job a little longer.
If the Cowboys win a Super Bowl then MM will make history. He will be the first HC to win a Super Bowl with two different teams
The current Cowboys HC is tied for 3rd place among active HC's in playoff wins. He is tied for 5th place among active HC's in average division rank. That is, where they place in their division at end of the season. He is tied with Mike Tomlin, Andy Reid, Sean McVay, and Bill Belicek.
Of, course, that's nothing compared to some journalist's opinion, represented by a cool looking chart.
I could have picked out their names from a hat and constructed a better "power" ranking.