My hometown of Boston, weirdly, had one of the nation’s sharpest population losses during the pandemic. According to The Boston Globe, citing the latest census data, Suffolk County, most of which is Boston, lost 28,850 of its roughly 771,245 people in the 15 months between April 2020 and July 2021.

This seems both paradoxical and wildly improbable, since Boston has one of the hottest housing markets in the country. Unlike Detroit, our population is not declining because people are leaving town and leaving behind vacant homes. So what gives?

I don’t have the house-by-house data to prove it, but it’s pretty clear that what gives is pervasive gentrification. Neighborhoods that used to be working-class are now trendy for affluent professionals.

Landlords raise rents, driving out larger families who are replaced with one- and two-person households. In addition, gentrification takes the form of large single-family homes that were converted to multifamily in an earlier era being converted back into single-family ones. The people who leave move out to shabby suburbs where housing is still cheap.

A good example is East Boston, known to locals as Eastie. For generations, Eastie has provided cheap, decent rental housing, to Italian immigrants and more recently to Latinos and Asians.

Even though it offered spectacular views of the Boston waterfront and was just a few convenient stops from downtown on the MBTA, Eastie was just too unfashionable to attract luxury development. But as Boston’s housing market heated up, that changed almost overnight.

In the past decade, about 2,300 new housing units have been built along Eastie’s shoreline, mostly luxury. Just 580 are classified as affordable, according to the Boston Planning and Development Agency.

As Eastie becomes trendy, landlords jack up rents, driving out longtime tenants, typically with larger families than the newcomers. The median home value in East Boston increased from $239,000 to $609,000 in just a decade. Rents soared along with it.

Similar patterns are occurring in other hot housing markets such as Manhattan, L.A., and Seattle, which also lost population. The inflation in housing prices has nothing whatever to do with the general inflation.

The scarcity of affordable housing is its own long-term supply crisis, reflecting decades of failed housing policies combined with gross income inequality (and the buying power of the affluent), and adding to the economic travail of working families. It is one more item of long-deferred action on working-class Joe Biden’s to-do list.