As I noted, the rental trend is one seen nationally. In the wake of the Great Recession, which destroyed the finances and credit scores of millions of Americans, many folks have found themselves unable to obtain a mortgage. Even for those who are able to obtain financing to buy a home, in many metropolitan areas, rebounding home prices have pushed many out of the market. Furthermore, in many areas it is exceedingly difficult to find and close on a purchase as a non-cash buyer.

Around the country, millions of would-be home buyers have become renters and there is not enough apartment supply. Rents are rising nationally and lots of people are struggling to cope, including in cities where there is no tech boom to blame. In short, the dearth of affordable rentals is not the result of the tech industry. It's the result of a broader supply and demand imbalance.