Boston's failure is thus purely a matter of policy and cannot be blamed on demographics or income.
Of course it is a matter of demographics. That is what the article is all about. The middle class is leaving the city because they can't afford to live there and because the quality of the public schools is declining. The gap between rich and poor seems to mimic a third world country.
Michael Barone"s article, The Realignment of America: The native-born are leaving "hip" cities for the heartland. goes into some detail on the demographics of what is happening.
"This is something few would have predicted 20 years ago. Americans are now moving out of, not into, coastal California and South Florida, and in very large numbers they're moving out of our largest metro areas. They're fleeing hip Boston and San Francisco, and after eight decades of moving to Washington they're moving out. The domestic outflow from these metro areas is 3.9 million people, 650,000 a year. High housing costs, high taxes, a distaste in some cases for the burgeoning immigrant populations--these are driving many Americans elsewhere."
"The result is that these Coastal Megalopolises are increasingly a two-tiered society, with large affluent populations happily contemplating (at least until recently) their rapidly rising housing values, and a large, mostly immigrant working class working at low wages and struggling to move up the economic ladder. The economic divide in New York and Los Angeles is starting to look like the economic divide in Mexico City and São Paulo."