Yes, this is true of some of the places, but definitely not all of them. Just look at most of the Midwest for an abundance of density-driven explosion in cost-of-living, but without any abundance of "high-paying jobs" to match.
I get that most of Hacker News is experienced with major cities (NYC, Boston, DC, Phily, SF, LA, Seattle, Portland, etc). And so it's tempting to tie housing costs to the specifics of that cities economy. But that's not the scary part. The scary part is looking at cities with "boring"/"normal" economies, and seeing the exact same thing happening to CoL over there.
Seattle can at least point to Amazon and say, "see, look, any random fresh grad can be making over $120k/yr at Amazon HQ!" to justify their insane housing prices. Indianapolis, Cincinatti, Louisville, and many more are increasingly getting up to similar prices, without any similar wages to justify it.
This article, for example, is about Ketchum Idaho. The person interviewed works two jobs to make $60k/yr and still can't find housing, because (according to Zillow, anyway) today's average sale price is over half-a-million dollars each!. Surely, Ketchum did not suddenly get an abundance of "high-paying jobs" to justify these prices. And Ketchum's total population has been basically flat for 20 years now, and today's estimate is still lower than their peak population from the year 2000, so there's no magic huge influx of new residents to point to to justify the prices either.