For sure. I mean, how much of the country it can spread to depends on how many people there are that can afford insane house prices, compared to how many that can't, and their distribution -- basically, as long as our society keeps moving to increase disparity in wealth and income, keeps moving to a bimodal distribution with the "rich" 10-15% on one hump separated by an ever-increasing amount of dollars from the rest.... the rich getting richer while the poor get poorer and the middle keeps shrinking... it'll keep eating up more and more of the country.
The only solution in aggregate is political, indeed. I didn't mean to suggest individual choice of where to live as a solution to the socio-political problem, but it can be an individual's solution to present situation that's making you miserable. Even that's not available to everyone, but just for those who can manage to get a job that pays well more than typical for the USA, even if not enough to live comfortable in Seattle. As long as you buy before the place "blows up", you're good even if it does. But if you want to reduce the chances the place you pick will "blow up" for a good long time, and are willing to live a place with less obvious regional amenities to do so, while there's no guarantee, we can all come up with places that seem like good bets. Des Moines maybe? Median house price $185K compared to $870K in Seattle.