No one drinks champagne for breakfast on $50,000 or even $75,000 in New York. Still, this is a vital shift: Over much of the last decade, most new jobs in the city paid less than $50,000. It was the core critique of Michael R. Bloomberg’s mayoralty by Mr. de Blasio as a candidate. Just last week, during a budget presentation, Mr. de Blasio emphasized how much of the city’s current expansion was in low-wage jobs, and said fighting “income inequality” would remain a focus of his administration.

Mayors have little power over big economic trends. They cannot print money. That does not mean there is nothing they can do. Mr. de Blasio has lobbied for a higher minimum wage, and is requiring developments subsidized by the city to pay higher salaries — both measures that Mr. Bloomberg resisted or blocked.

Yet Mr. Bloomberg also put his shoulder against inequality; history just takes its time telling unexpected truths. He said the city’s economy could not rely simply on Wall Street, because it would always go through downturns. The city used tax cuts to lure back the film and television industry, which had taken many of its good-paying union jobs to Toronto.

It developed land north of Bellevue Hospital Center along the East River into a biotechnology center that is now 310,000 square feet of lab space. Construction has started on a two-million-square-foot campus on Roosevelt Island for graduate engineering studies that will be run by Cornell University and Technion-Israel Institute of Technology. The city encouraged the expansion of three other universities for technology research and study.

In its first 400 years of European settlement, New York grew because its superb natural harbor made it a hub for trade and manufacturing. With the decline of the waterfront and factories toward the end of the 20th century, New York needed new advantages. It depended heavily on the finance, insurance and real estate sectors — FIRE for short — which was good for high-wage earners, and created a service and retail economy for people at the other end of the ladder. But with every bad downturn, the whole city was knocked around. The efforts to diversify worked, as a front-page article in The New York Times on Monday noted.