This is true, but one significant difference between the two is that (I'm guessing) 30-35% of Michiganders who are sports fans root for the other big state school, and Bo wasn't a "God" to all of those folks. Ernie, OTOH, was beloved by a broader cross section of people.
One can surmise that was never a fight Bo would win, even if he was a God in Ann Arbor.