This is a bit sad for a number of reasons: my dad used to have a setup when I was a kid, I had sets as a kid, and the Tech Model Railroad Club (https://en.wikipedia.org/wiki/Tech_Model_Railroad_Club) was a source of inspiration to me as a kid with a computer and a train set....
It's sad to see this appearing to trail off, but I agree with a previous poster, I think the retirement of more baby boomers and their nostalgia may yet give the market a boost.