I think there are two questions here: 1. Will he be successful? 2. Will he beat Ohio State?
It's hard not to be a success at Michigan. Why? Facilities, huge stadium, strong alumni program, loyal following, money, tradition.
You can scoff at the tradition part, but even if you go back to 1920 and compare its something like 64-57 in their favor. Those four losses '21-'24, cheating or not, still sit on the books.
Do I think Whittingham can survive 3 seasons? Yeah, because the rest of the Big Ten and the MAC schools that will make up his schedule all but assure him of a winning season and at least one 10 win season.
Do I think he'll beat Ohio State? Think of how fast this season's game could have been 14 - 0. It was still a game into the third quarter and not a sure thing until half way through the 4th. They will always be able to draw kids either from recruiting or the portal because of FSAFMT.