Good article on the rise and (current) fall of the center-left. This bit here is definitely a thing that has been happening.

Yascha Mounk--director of the Tony Blair Institute for Global Change--wrote that the Democrats should focus on "states where appealing to the white working class is not as important as increasing turnout among minority groups and appealing to moderate voters in the suburbs." Note the slippage: whatever program will appeal to the entity known as the "white working class" will not appeal to "minority groups," who are joined together in this analysis with "moderate voters in the suburbs."

It's why whenever Bernie (etc) says "working class", pundits hear "white people".

The danger that the Democratic Party and elite liberalism now face is that they cannot conceive of the American working class as it actually is, insisting instead on addressing a specter from decades ago. The right-wing hard-hat, the eternal Reagan Democrat--such anachronistic images provide a way of not engaging with questions of class inequality. So long as these ghostly figures are what "working class" means, there can be no working-class force in political life, and the cycle of programmatic dilution and mass demobilization can continue, with increasingly horrifying consequences.