I can say from first hand experience that this is NOT the case in the part of Turtle Rock that my parents live in. The neighbors, most of whom are older and retired, have a great community. They do a group walk every morning, go on weekend journeys and have blockwide events all the time. I wish I could live in this area, but it is way out of my $$ range.
Like I said, these are older people who have lived here a long time. Many of these people are original owners from when the homes were built in 1976. As younger families move in, they don't join the community. They are missing out. Too busy working over time to pay for the BMW perhaps? Language barriers? Who knows.
I really think that the older parts of Irvine still have that great charm and great people in them. Any home built after 1985 is incredibly generic. Irvine, Riverside, or Sacremento, it doesn't matter, all of these new suburban tracts look the same. When you stand in University park, Turtle rock, or the lakes of woodbridge you know you are somewhere special. When you stand in Westpark or anywhere newer, you are in generic suburbia, USA. Why pay a premium for that?