It's hard to win at Iowa State, despite the very faithful fan-base. You're a long way from the great recruiting fields, and as I understand it there's not all that much in Ames, IA, to attract kids from a thousand miles away to come there.
Within the Big 12, Matt Campbell is well respected, and is considered to be doing more with less than any other coach in the conference.
By contrast, the Jim Harbaugh who is being discussed on this board seems to be doing less with more.
That was the rap on Mack Brown at Texas. "Coach February" he was called, in recognition of his recruiting success that did not fully translate into on-the-field results. Bob Stoops' OU teams laid some of the worst beatings in UT history on Mack's Longhorns. But Mack won the BCS national championship for 2005, then coached for another one after the 2009 season, and might have won that one too had Colt McCoy not been knocked out of the game.
There's a lot more to being a head coach at a blue-blood program than merely coaching ability, as previously outstanding coaches so often find when they take a position at one of the blue-blood schools. Coaches like Rich Rodriguez and Brady Hoke. But I'm confident that Matt Campbell can coach a football team. Could he run a program like Michigan football, with all the other things above and beyond coaching that that job entails? Who knows?