Oh, I don’t think there is one unified “they”; I think one part is marketers constantly trying to co-opt what is “cool” and then sell it back to people. If giving people a sense that “my generation” spends money on these goods and services and “that generation” does this, it serves the purposes of marketing, not the targets of that marketing.

And pols use code-switching in much the same way. I think elitists are going to keep this going - a populace that is atomized as much as possible is going to be easier to keep pitching the worst aspects of capitalism to, and if they think “that generation” is the source of their ills, (rather than taking a close look at who wields all the power and the money) so much the better.