I didn't understand what made otaku loves the denshas to the point of creating masterpieces liek this: https://m.youtube.com/watch?v=I0yYijKM5S4
But ever since Im in Tokyo I'm starting to get it.

They all belong to different companies, have distinct design according to each line and its quite fascinating from an engineering point of view. Typically the kinda fascinating thing that oyaku obsess over. Sometiems when you wait at the 踏切 youll see a young tetchan grab a camera when the train is coming and stop once its crossing the road. Theyre very interested in the front of the train, its like its face. Trains are the closest to IRL mechas!
Also for each train/line is associated its stations which are a big part of the charm too: some trains are associated with work, other with travels and vacations.