Blakeney was a special case.
First he had been up in the upper echelon and while maybe didn't have totally clean hands, he was also likely picked to be the guy to take the fall for others.
Second, there were schools who weren't going to touch after that so the schools who did approach may not have been schools he ever wanted to go to.
Third, Troy took an interesting path that had to be professionally challenging and interesting. Not many people get to lead a program from one classification to another TWICE at the same school.

If Troy had stayed Division II or FCS, who knows if he would have had the same thinking.

Guys like Blakeney are more unicorn than horse, it happens but in general coaches are like milk, they have a short shelf life at a school.

Never hire a guy planning to keep him two decades. If it works out and he's successful, that's wonderful, but if that's your goal then you need the guy who isn't good enough to advance but too good fire as a general rule.