Who gets to define the Zeitgeist?

Chris Morris's Brass Eye was one of the best observed comedies ever (well, until Nathan Barley came along). I'm amused that I hear engineers refering to certain production people as Nathan Barleys!
Anyhow - I read this piece in yesterday's Independent and wondered why it's that certain segment of the white, middle-class, decedant types who get to define the times. Just read the text and think back (if you can!) to the eighties. I had a brilliant time - I was studying my degree, graduated, went to work at the Beeb and got married but I was very aware that for many it was a terrible time - if you were unemployed (it hit 4 million), if you were buying a house (interest rates hit 16% - oh yes, I remember it well!), if you were a miner, stealworker or trade-unionist it was terrible. Most of us weren't going to

...extravagant parties most weekends, and weeknights slumped with the rest of the media world in Groucho's listening to Julie Burchill hold court or bitching about some editor or other.

I had a similar chat with my Mum A couple of years ago - we'd just seen a BBC documentary about the sixties featuring Joan Bakewell going on about what a liberating time it was. My Mum (who grew up in a small town in North Wales) has the view that there is a huge gulf between her experience - just getting on with life, working, having kids etc. and the Carnaby Street idea of the sixties - in truth all that stuff only really happened in Carnaby Street!
Oh, another thing - what is a PR guru?