But there’s a little gap today, so here’s #3.
Someday, when all vehicles are autonomous, it seems to me that things like stoplights will no longer be necessary. If the vehicles are aware enough of each other, traffic could steadily stream through an intersection in all directions simultaneously without anyone having to stop. But in such a world, if some backwards traditionalist insists on driving the old-fashioned way, they’ll do nothing but cause accidents. Is there a specific tipping point where these larger-scale infrastructural changes can happen organically, or will we have to hold out until manned vehicles are banned from public roads (either by the government or by insurance companies)?
This is a good question and nobody really knows the answer.
My best guess is that we’ll see these changes happen organically, but also very slowly.
A good comparison might be with electronic toll tags, although admittedly these are a much less disruptive technology.
According to Wikipedia, electronic toll collection debuted in Norway in 1986, side-by-side with cash toll collection.
It took 27 years before cash toll collection ceased on San Francisco’s Golden Gate Bridge. To this day, 30 years into the ETC era, half the toll lanes on the San Mateo Bridge (the closest Bay Area bridge to me) are cash lanes.
Infrastructure moves slowly.
So how would this happen with self-driving cars?
Maybe vehicle-to-vehicle communication will get good enough that cars can talk to each other and synchronize their movements. At first, it might just be Teslas talking with Teslas, and Fords talking with Fords, but maybe they’ll converge on a protocol over time.
Getting traffic lights to change on-command is a harder problem that know little about, so I won’t speculate there.
But my guess is that self-driving cars will have to operate in the world as they find it, not in the world we might like to have.