If it was a bunch of blue states getting the benefit, but we are talking about one plant in Michigan.
So, with a sample size of one car model, one manufacturer, and one state, yes it has skewed blue. But Ford uses UAW labor and is already hiring up and investing to build the Ford E-Transit in Kansas City Missouri. Its the same plant that makes the F-150.
I'm not arguing at this point, I'm just saying it is a little more gray than a red/blue split. As far as union/non union...yeah, I suppose I would be hard pressed to argue that it is fair, but I think we'd be better off if workers were generally unionized, so I'm biased. Yes I know there have been union corruption scandals and the like, but we don't toss the baby out with the bath water.
Side point - I really don't like the red state/blue state thing. The reddest state has a lot of blue, and the bluest state has a lot of red. Wyoming is the reddest with nearly 70% R 16.5% D. The bluest is NY at 50.4 D, 21.8% R. We ignore a lot of people when we characterize a state so simply.