No matter what the comments were or weren't, he was criticizing Ohio St and promoting ND - which he should. I view it as him riding for the brand. Loyalty to the brand is admirable.
Jim Hardeeharbaugh made similar comments when he was at Stanford about scUM. It's part of the deal being a head coach.
If MF's comments about Ohio St being the "wrong" choice and he regrets not going to ND, well, that's unnecessary and intentionally provocative.
Still, if he is wildly successful at ND and becomes the head coach at OSU someday, I think we will forgive and forget. After all, we warmed to Urban Meyer pretty quickly when he was hired.
But if his head coaching career is disappointing, and he is not wanted back in Cbus, he may have burned some bridges he might regret later. His dad loves Ohio St - and I think Marcus does too, but he should dial this rhetoric down a few notches.