I'm not so sure. I'm in the Midwest, and housing shortages and gentrification are extremely prevalent problems here too, in almost every city with employers. It's a major problem even for some absolutely tiny towns - http://www.freep.com/story/money/real-estate/2015/12/21/hous...

Sure, the scale is way smaller than coastal cities. But if you adjust the prices to match the incomes, the unaffordability problem is roughly identical in terms of pain. A Michigan $300k urban condo is basically as unaffordable as a Seattle $600k condo, once you notice that Michigan incomes are roughly 50% lower than Seattle, on average.

Sprawl is cheap, that's absolutely true. But it's also sprawl -- with all the problems that entails. The only cities I know of with "huge housing surpluses", are cities that have majorly failed in some way (like Flint).