> We can not design self-driving cars to the safety standard that is required for railways.

That is completely false. PTC does that, and we've had it for several decades. There are several self-driving cars operating in the world right now. I have never heard of a PTC system causing accidents; those occur in places where the system isn't required (like entering Grand Central).

You keep pretending that avoiding train collisions is too magical to achieve with current tech, but train traffic is easy to limit (but slightly harder to optimize), and systems exist to do that, because rail is unique amongst all forms of travel: if you drop speed to zero for any trains at risk of collision, they are safe. Planes will plummet; most cars are human-operated and you can get rear-ended, etc.

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

And they somehow work with radar, lidar and GPS from inside the train? No they work with classical block based systems and on signalboxes. So all the safety systems are outside of a train.

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

Huh?? Railway interlocking exists for more than a century. It's very safe and I didn't wrote anything contradicting that.