Also, if you see some of the articles and movies from the 60s/70s, they were saying all this stuff about baby boomers too.

I saw somewhere where they gathered examples of "people in their 20s don't want to work the same way the folks in their 40s did at their age" dating back to at least the mid nineteenth century.

I've also seen the point made that a lot of the assumptions about the boomers having it nice and easy comes from media products that strategically wanted to frame things as doing great, as they thought that's what drove media consumption, folks wanting to feel good about the world. Now the general understanding is keeping people in an eternal state of panic and dread will keep those eyeballs glued to the product. Bad stuff happened back then too, and plenty of it should have been a more prominent source of dread by today's standards.

Further, to the extent it was true, it was mostly a USA thing coming from a couple of phenomenon: -Every other major industrial economy had been severely impacted by World Wars I && II, with USA barely having a scratch. So for a good while, most of the economic activity favored the USA across the globe. -Factors like racism where huge swaths of the USA population 'didn't count' when people were thinking how good things were going.