If anything Michigan probably ends up being to Trump what Indiana was to Obama.
Iowa could be as well.
No, it couldn’t.
The thing that annoys me about the IN 2008 comparison, is that it ignores the fact that both IN and MI are states that are trending away from the Democratic party. I could see MI being a tilt D state in the 2020s, but it wouldn't make any sense for it to be a fluke. It will continue to be competitive for the same reasons that IN is no longer competitive.
Also, the idea that IA in 2020 and IN in 2012 (or even IA and MI in 2020) are in any way comparable is ridiculous. IA could certainly trend Democratic, but it’s not going to revert to being a Democratic-leaning state several points more Democratic than the nation as a whole, and it’s definitely not going to vote more than 5 points to the left of OH.