This is an attitude.
It rejects every optimistic, positive and clear approach as being childish. Behind such views, there is no bright brain at work but deep-rooted complex of a life-long loser.
It comes with a beautiful mask of "experience".
Beware! it's **** among the attitudes.
Though not specific to any age group, but people who claim to be more "mature" have been found to be more prone to its attacks.