Whatever it is, young people these days evidently don't "get it". I can't remember that last time I saw a school-age kid riding a bike in my area. It seems as though riding a bike, especially an old steel road bike, is about the uncoolest thing someone their age could possibly do!
The good part is that vintage bike prices will continue to plummet. At this rate, in 5-10 more years, no used bike will be worth more than $100, regardless of brand or quality.