Old, dense, transit-served cities like San Francisco and New York have excessive restrictions on new housing construction, making them increasingly inaccessible to all but the 1 percent. Newer, sprawling, car-centric cities like Dallas and Atlanta facilitate new development, helping to maintain lower housing costs.

This is the argument advanced by economist Ed Glaeser in his much-cited 2011 book The Triumph of the City, a paean to creative-class urbanism written by someone who could afford to live in Boston’s Back Bay but instead chose suburban Weston, outside the Route 128 beltway that defines the metro area.

There is some truth to these basic facts, but their interpretation has led to a pernicious claim about urban development: that the construction of any housing stock at all, even luxury condominiums, will relieve pressure on the housing market to an extent that will keep cities “affordable.” This reliance on a false cause and effect has become a common justification for urban gentrification. Once the new luxury condos are built, the argument goes, truly wealthy city-dwellers will move into them and leave open the market-rate apartments meant for good old middle-class families.