Michigan State is sort an interesting situation to watch unfold.
Dantonio is crusty and not very charismatic, but he had a lot of great D line talent and high level WR and RB recruits for a many years , and much of that pipeline seems to gotten clogged up.
Michigan getting better has hurt, I think losing Narduzzi to Pitt is a big factor as noted previously. Their defense used to Iowa like, with a little more flash at times, but that has fallen off.
The bad PR from the molester gymnastics guy Nasser? probably has had an impact as well, as the general feeling was that MSU was pushing the limits with recruiting and tolerating a lot of bad behavior to hold onto risky, talented football player over the years. With the spotlight on MSU, Dantonio probably cannot get away with much anymore.
With one or two more underwhelming years, he is finished for sure.