Is it? The theory of block signals and path signals don't change because AI was invented. And I have my doubts that AI could do better than path-signal algorithms.

https://en.wikipedia.org/wiki/Railway_signalling

OpenTTD players, wassup? You can run these block signals / path signals in video games. Its a bit complicated to setup and the terminology is arcane... but the algorithms aren't so advanced that they require "AI" or anything. (If at block signal, wait until exit signal is ready. Etc. etc.). Its actually pretty fun (OpenTTD is a videogame built around these signals!!), because if you mess up your signals, you get deadlocks and/or "race conditions" (aka: risk of a deadly crash). But once you get used to the methodology, you can build incredibly complex junctions that automatically and safely routes trains everywhere.

That's why you had legions of railway nerds playing with trains in their basement all day: they're trying to get their path signals / block signals / chain signals correct so that those toy trains traverse their toy-tracks automatically without crashing. These concepts were like, from the 1930s or something (Path signals are newer)

EDIT: Apparently "before 1923": https://www.amazon.com/gp/product/117705681X. Definitely an ancient and arcane art of old wizards. Railway engineers were dealing with semaphores, race conditions, and deadlocks __LONG__ before us programmers even existed!!