Let's do Leipold and Bohl. They both had dynastic success at lower levels of college football in their previous jobs, so they make sense as a comparison. Fun fact: they also worked together on Frank Solich's staff at Nebraska from 2001-02.
At UW-Whitewater Leipold inherited an excellent program whose only losses the previous two years had been in two D3 national title games. He created a dynasty, going 109-6, fastest coach to 100 wins in NCAA history, and won 7 national titles in 9 seasons. My brother was at UW-Oshkosh during this period, often the #2 team in the conference, and he said Whitewater just effortlessly outclassed everybody. This is D3 football of course, no scholarships, not really recruiting in the commonly understood sense, but this was an amazing level of dominance.
He got his shot to try his hand in big boy football at Buffalo, considered one of the toughest jobs in FBS. I say considered because both Jeff Quinn and Turner Gill before him had had intermittent success, he didn't inherit a total dumpster fire, and he didn't have instant success either. But their 10 win season last year was the most in school history, and they look like one of the better teams in the MAC again.
Whitewater, WI is just across the border with Illinois, they had Illinois kids on the team up there, he'll know some of the area HS coaches. The thing that makes me a bit skittish with Leipold is just his affect. He's a very low key, unassuming guy, with maybe a bit of rube about him. Spend any time in Wisconsin and you'll meet 1000 Lance Leipolds. How would that play here? How would that play in big-time recruiting, with big-time assistant coaches, big-time media, big-time everything? He is not the guy you'd choose from YouTube videos, put it that way.
Bohl got fired as Nebraska DC after their first non-winnng season in 40 years. He took over a then D2 program at North Dakota State, moved with them into FCS, and slowly but surely created a monster, ending with three consecutive national championships. From there, Wyoming almost didn't seem like enough of a step up (his successor Chris Kleiman jumped from NDSU to Kansas State), but he has taken a tough job there and had some success there too.
I think the case against Bohl, other than his age (61), is that his Wyoming tenure isn't THAT impressive. That's not a program that's had a ton of success over the years, but he didn't take over some smoking crater from Dave Christensen. He's 31-36 in six seasons there, never winning more than 8 games. Per the Sagarin ratings he's never had a team there better than his last 3 NDSU teams, not even close really. Being a nerd about these things I've always been watching him waiting for Wyoming to take off, but they really never have, including that year with Josh Allen where they came in with a lot of hype.