I'm a fan of the Midwest in general and love the seasons (even in MN) but I don't know that the jobs are there. My friend in Madison (a very intelligent "ABD" who, as often happens in math PhD programs, burned out) got $45,000 in his first programming job because his company had no competition. Even now, I doubt he's higher than $90,000.
As for leaving SF/Boston/NYC, I moved to Baltimore, which is not the Midwest and actually not that cheap. The two-body problem is a big part of why the "star cities" are so attractive. I like Baltimore-- it's way better than its reputation, although that ain't saying much-- but when I next search for a job, I'll probably find more outside of Baltimore than inside. Also, there's that two-body issue. This move has been good for my career but so-so for my wife's, because there aren't many good companies here. We shouldn't have to choose between one career or the other and, in the long run, we won't. The costs of housing in San Francisco and New York are fucking criminal (literally, if you look into the NIMBY issues) but knowing that both you and your spouse will be able to find high-quality jobs for 10+ years is the draw. I'd rather live in Minneapolis than San Francisco, but I'm pretty sure we could live in San Francisco, career-wise, for at least a decade. Are there going to be VP-level-but-mostly-coding machine learning positions in Minneapolis in 2024? Not a clear call. And cross-country moves are stressful and just get harder with age.
Of course, San Francisco and New York spit you out if you don't become, at least in pay grade, Director-level by child-raising age. To be honest, I don't think we'll move to either of those cities when we next relocate, because even though we'll be able to afford it the expensiveness is horrible for the culture. We ranked cities independently and Seattle topped both of our lists; it's affordable (if not exactly cheap) and beautiful and neither of us has a problem with 50-degree cloudy days. (In MN that was called "Early May".)