I guess you are defending him?
Yes.
He doesn’t beat good teams. That’s facts.
Yes, but those aren't all the facts.
First, you are defining "good teams" to mean only Ohio State and Alabama -- because Harbaugh has half the time or more beaten Florida, Penn State, Wisconsin, Iowa, etc.
Second, teams -- on *average* -- beat the opponents they are favored to beat and lose to the opponents that are favored to beat them. It will take more than 5 years to go from 2014's Michigan (5-wins, #37 recruiting class) to one that is regularly favored against the likes of Alabama and Ohio State.
Third, Harbaugh at Michigan is a top-10 coach in winning %, and from 2016-2019 is one of the top recruiters. Only 4 teams recruited better than Michigan in that period: Alabama, Ohio State, Georgia, and LSU. Michigan during that period is about the same as Clemson and Oklahoma.
Fourth, if its so easy and likely to do better than Harbaugh, what happened with USC, Florida State, Texas, Miami, Tennessee, Arkansas, South Carolina, Nebraska, and Ole Miss? Those are all programs that have plenty of money (revenue of $80-130 million/year), good fan bases, desire to win, good football history, etc. Look what happened to Michigan prior to Harbaugh. It is easy for changes to be a disaster. Yes, sometimes schools make a change and get a superstar -- Smart, Riley, maybe Orgeron -- but *way* more frequently the opposite happens.
Fifth, Dabo Swinney lost 5 times in a row to rival South Carolina (2009, 2010, 2011, 2012, 2013) -- and South Carolina is no Ohio State. It took him 5 years to get to 11 wins with Clemson, and 8 years to get to CFP level. During that time, people invented the derisive term "clemsoning". If they had given up early, they would have lost one of the greatest coaches in football history.
Sixth, outcomes in football are subject to a high degree of variability. Things in 2016 were very, very close to being dramatically different for Michigan. But for a miniscule change here or there in 2016, and all of this would be a completely different conversation.
Seventh -- and perhaps most importantly -- I see Harbaugh making adjustments each year in response to what didn't go well a previous year, and many of those do work out. It gets hidden in the variability of win/loss outcomes, but it is progress and, I think, eventually will show up in win/loss.
For these reasons, I like Harbaugh being at Michigan.