Of course, the transition is quite broad and it has different sides, one of which is philosophical. Modernists did expect material progress, but materialism was itself a metanarrative. The postmodernist would point out that having enough material goods to live on doesn't suffice to make you happy. So the modern myths were as simplistic as the religious dogmas they replaced.

Marxism was another modern, scientistic myth: class warfare would inevitably usher in a communist paradise because of history's progressive logic. With the collapse of the Soviet Union, who believes in anything so inevitable now?

But I agree that much of the skepticism comes from idleness and anomie, from a felt lack of purpose. Myths are what sustain the impression that life is meaningful, and skepticism undermines both the myths and the uplifting sense of being at home in the world. Rampant objectivity is alienating.