I think you're confusing family oriented vs non-family oriented. Of course people with new families are going to focus and talk about them more that world economic conditions. That's not the topic though.

Sticking with the Old vs Young subject matter:

If anything, research has shown it is younger people that have a higher inward focus. In fact unless they're particularly politically conscious younger people are much less likely to speak about those far reaching or even global issues. Of course there are exceptions, sometimes large political issue make their way into younger subculture as topics of interest for a short time and there are some very politically motivated young people.

We're talking about larger trends here of the population as a whole. The topics of interest for younger subcultures often tends to be precisely non-political (pop culture, entertainment, school, work etc) vs older subcultures which is much more often political. This is heavily reflected in voting trends among age groups.

What young people are though is socially conscious. Research has show that people are often more tolerant of other differences when they have regular and normal interactions with people of different backgrounds, life styles, beliefs etc.

Since the general trend has been towards more diversity as time goes on and cultures mix, young people are naturally going to have more tolerance and acceptance. On a similar note, as you get older you have more ability and power to choose whom you associate with. People that gravitate towards regular interactions of less diversity and similar beliefs are likely to become less tolerant and more conservatives in their beliefs.

This is show in studies where people do exactly that, a group of like minded people will feed of each other slowly making the group as a whole more conservative as time goes on. Oddly enough this is a know effect in group therapy sessions that need to be actively countered, "well I was talking to Bill he said it was fine to hit my wife." Conversely grouping people in a more diverse way trend to make groups more moderate as whole.