With this like many things it come down to point of view. Those who want trains to be as close to the real deal as possible have their passion in that point of view, they love having engines the prototype had, they love scale or near scale sized equipment , they love to run simulating what a prototype may do, others on here love simply 'playing with trains' , others love recreating the toy train experience of their youth, and as they say, whatever floats your boat. The problem with passion is it often can get translated into "I love this so much, everyone else should share that' kind of thing, true of religion, politics, or food for that matter (where, for example, lovers of true NY Deli food would take out their machete and cut the hands off of someone eating corned beef on white bread with mayo.
With three rail trains, with the exception of Manhattan streetcars (well, okay, not really a middle third rail, more like a trough) and some rare exceptions, they are not truly prototypical, but so what? I appreciate someone who loves to try and model the prototype as much as possible, and to me, given all the compromises we make (for example, even in N and HO, it is very, very difficult to model prototypical curve radii, even the broadest curves modelers use are often way sharp by prototype standards), or details too small to model, the art of model trains is the art of compromise. We build hidden staging yards to simulate trains coming from far away, for example, and we use tricks to make the layout seem like a railroad, rather then a relatively small length of track that for most of us, loops around and around.....so if we run three rail track that has impossibly tight radii by prototype standards, it is part of the compromise process, you live with limitations. The beauty of the hobby is you have that choice, there is no equivalent to building departments or homeowner federations or condo boards to tell you what you have to do, we have the freedom to do as we wish.
This isn't limited to trains, someone else mentioned car enthusiasts. With "classic cars", there are people whose mania is 'original equipment', they want cars with matching part numbers, everything just as it came from the factory, then there are people who love a 67 GTO but do things like put electronic ignition on it, put modern 4 wheel disk brake kits on it and so forth, to make it more reliable than the original; the purists can get their noses out of joint, grumbling how it is 'desecration', but the people who do that enjoy the car as it is, that is their right; and if as the purists will say, it will 'ruin its value', that is their choice *shrug*. It is like those who grumble in toy trains when people weather their equipment or put more details on it, arguing it will 'ruin the value' or some such; You might consider someone weathering an original 700E from the 30's is killing its value, but that is their right. One thing we have to keep in mind, as beautiful as we think these things are, these aren't one of a kind pieces of art, we aren't talking about spraying graffiti on the Mona Lisa or putting gym shorts on Michelangelo's David, we are talking things that though mass produced, we love as if they are great,rare art, but in the end they are simply that,mass produced items we love. Feelings are okay, I have seen old small sports cars that someone shoved a 350 engine into and I think it is idiotic, but I also can appreciate it is something they wanted to try and I wouldn't tell them that I thought it was idiotic.