Bowling Green is an also-ran...they aren't even in the top 5 of football schools in Ohio. The fact that Urban Myth got them to where they were when he left wasn't something to merely sniff at.
Utah pre-Pac 12 was a dumpster fire until Meyer came along...it was really the foundation that he laid there that actually got them into the Pac 12.
Even the Gators were also-rans under Zook, and as much as it pains me to say it, Meyer turned them into a powerhouse before he suddenly left...of course, UM and FSU being in the proverbial dumpster fire status had some part to play in all of that, too, as UF really filled what was a huge vacuum in the state.
Taggart isn't too bad of a coach, but to crown him among the GOATs as a program builder is a little much. He wasn't too bad at Oregon, but when they lost, they lost in pretty spectacular fashion.
I would say that USF was an easier job than BGU or even Utah, considering their access to local talent around the state...a 3rd tier athlete in Florida is better than a 2nd/even 1st tier athlete in a state like Utah, or the scraps that Bowling Green would have to fight for among all of the other lower-tiered schools in Ohio.