I am involved with the vintage model train scene and the prices that Hornby 0 Gauge, Hornby Dublo and Trix models are fetching are nowhere near what they once were. Not that value is my motivation, but it is a clear indication of the diminishing level of interest and interested would be purchasers.
Many modern manufacturers have really neglected to invest in the child friendly train set market for many years, so as well as the older folks 'falling off' at one end, we have fewer younger folk 'coming in' as well.
Once it was the norm to have a trainset when you were a child, now, (as has been amply explianed in this thread) it is not and a lot of children and teenagers have no interest.
I think we are heading for an adult hobby, but if the core of the hobby continues to decline, what will that mean for manufacturers and ranges/choice in the future?
I guess that modern specialist manufacturers who can adapt to small batches will survive,
but large batches for the mass market could well on the way out.
James