[i_am_jl]

>It’s not hard to imagine a new type of safety cone that has an explicit sign for autonomous vehicles to stop far far away.

Two things:

The promise of self-driving cars is that they can operate themselves in an environment not specifically designed for them. If that promise is broken, and it's the position of the industry that things like traffic signals, construction, emergency services, road markings etc need to be modified for functionality with self-driving cars then I think public will to accommodate them dries up quickly.

That being said, I can imagine having a lot of fun with a physical token that can remotely stop an autonomous car.