> but you can't say that it has ever happened in Japan.
That sounds very unlikely to me, and in fact Wikipedia indicates otherwise: https://en.wikipedia.org/wiki/Shigaraki_train_disaster
This you? Who's fault is it then? You said the tech doesn't exist (lets take that at face-value for the sake of your argument), so then if not tech, then what? You're just left with people. So are you saying it is their fault or not? Or is it just nobody's?
In addition: https://news.ycombinator.com/item?id=50297950 https://news.ycombinator.com/item?id=50293093