'We don't talk to anyone we don't know.'

When this movie came out I remember reading something about whether it reflected Generation X accurately; and one Gen Xer quoted said that he (or she) thought it did, including the characertistic "We don't talk to anyone we don't know." I'm a Baby Boomer and I'm wondering if that's true; and if so, do you think it is an attitude that has been carried on by GenYers, etc.? I've been thinking about it because the apartment complex where I live has recently become heavily populated by people in their twenties, who seem never to talk to anyone else, particularly "codgers" like me. I'm not particularly "friendly," but if I meet another tenant at, say, the laundry room or the mailboxes, I'll usually nod hello or something, and these kids go into "the zone" (i.e., if I don't notice you you don't exist). In the rare times where I've spoken to one of them about some problem in the complex, their reaction is a definite "Oh God, now I HAVE to talk with this being."