>>968701That's actually a very good question, which cannot be answered in one sentence since there are multiple things that can lead to this kind of fascination.
I guess for me it's a mix from father influence (he was commuting between 50ies and 70 alot by train and talking alot about what he experienced), the mechanical fascination, aestetics, fondness of traveling, interesting stories and facts revolving around the topic....that's what came into my mind right now. I cant deny that it is somehow an interest that lies within my family line, yet I am the first one, who sunk into this topic real deep with heart and blood.
And yes, this hobby does also have lots of autists (does also apply to model railroaders). I'm talking from my own experience. Heck, I wouldn't even deny that I have this kind of autism in me too. But in opposite to some other annoying fellows, I have learned to keep it for myself and know where I can let it out to which extent without looking like an idiot. But in the end, you will find them in every field of interests. It's more of a thing how each individual deals with his personal grade of autism.
So whenever I still hear the TB11+tubocharger sound of a german class 218, my inner autist is jumping, but I know that others do not share this interest and I respect that. Hence why the above average anifag in my country tends to me more obnoxious than a trainfag. They are alot younger and still need to learn that not everyone likes chinese cartoons.
https://youtu.be/MFHOST2dI7M?t=4m49s 
