Based on how the hobby has evolved over the last 25 years and thus based far more on fact than on fantasy, the next 25 will see the number of hobbyists shrink to only a small fraction of what it is today, perhaps even back to the levels where the hobby was in 1945. This will be as the result of a number of changing societal factors which are already clearly apparent.
The pricing of all hobby items will escalate to the point where only a relatively well off segment of the population can participate fully and have complete layouts. Technology will allow every item to be done as an extremely limited run...perhaps no more than 100 units at a time...yet still be profitable to the manufacturers because of the prices charged the buyer. Personal craftsmanship and advanced modeling skills will have dwindled to almost nil, their place taken by the store bought, highly advanced technology offered from the manufacturers.
Nearly all layouts will be assembled from commercially made, totally finished-out, modules that can go together in a number of possible arrangements. Personally building your own individual unique layout of any size from the benchwork up will be an looked upon as an anachonism. The trains, themselves, will be completely operated through a computer program, without any need for human operator intervention. You will plug-in a pre-written chip, or maybe occasionally punch in yourself, a set of routing instructions for the train, hit enter, and it will go dutifully through all its stops, setouts and pickups automatically as the "operator" simply stands by and watches.
"Model railroaders", themselves, essentially will have become computer/electrical technophiles, no longer skilled hobbyists in the way we understand the term today, basically using someone else's (the manufacturers' or some custom builders') layout and equipment, much as is done with virtual layouts on-line today. Virtual layouts, in particular, will constitute a very large segment of the hobby and be in great demand, again because of societal changes and time limitations. They will replicate all the famous layouts of the past for you to call up and play on...in full 3-D, with prototype surround sound and seen from a viewpoint as if the operator were 1/87 scale...and riding in the cab, of course!
CNJ831