I know there is a segment of the 3-rail hobby that has decidedly moved towards the prototypical scale direction. Maybe it's just nostalgia. Or the familiarity of what I grew up with. BUT to me, this IS a Lionel train layout. My imagination adds in all the other details!
I think there are plenty of people interested in traditionally sized postwar style trains. A lot of people just would not have the space for scale sized "O" gauge trains.