> That is completely false. PTC does that, and we've had it for several decades.

I think you are misunderstanding the sentence you quoted.

It says something about the safety of self-driving cars. That is they don’t meet the standards required for railways. In other words the expected safety for a self-driving CAR is lower than the expected safety of a RAILWAY. (Caps for emphasis, sorry about the shouting.)

Your comment reads as if the quote claims that we cannot make “self-driving trains”. It does not say that.

> You keep pretending that avoiding train collisions is too magical to achieve with current tech

I don’t think that they do that. Definietly not in the comment you responded to.