You can get out of a car on railroad tracks. However, “safely come to a complete stop” includes turns and freeways which are more serious concerns.

That’s why I said 30 seconds / 30 minutes not 3 seconds. The idea is to go to somewhere safe and pull off the road not just slam on the breaks and hope your not on a curve.

A narrow case easily accounted for

Enumerating all the narrow edge cases has proven surprisingly difficult.

but train tracks is not that kind of edge case, tbh, it's so vanishingly situational

"Train tracks" are a subset of all the edge cases in the set "car can't just stop and stay stopped and that's safe".

In case of self-drive malfunction you still have a gas pedal under a human's foot