Eh, it's probably good to have regardless?
It's less about being careful around the car and more about how you might interact with it. For example, honking the horn or flashing your beams wouldn't have the same effect. On that note, it might be nice to have some way of telling a self driving car to temporarily use elevated sensors or something, the same way a horn tells a driver that something is wrong. As long as there's a way to prevent abuse of the system
I don't know much about these lights, but we COULD use some new standards in general with how many things have changed with cars in recent years. Brake lights on electric vehicles being another thing to consider.
That "gentle horn" everyone wants being another
That's where I'm at. Why not both? Redundancy is good,
Paper copies are good to have till they're no longer necessary (edit: and apparently these aren't necessary anymore)
Digital copies are also useful for obvious reasons