I personally think within 5-10 years, forward facing cameras will be mandated on all vehicles, starting with commercial/heavy duty vehicles. Yes, there's some degree of a privacy argument with it all, but the safety and liability boosts dramatically outweigh them.
Assuming that happens, either your suggestion could also happen, or a visual solution to the same thing could also be in play.
Who handles liability if you get into an accident? When does it take control of the vehicle away? The most likely scenario is the car pulls over safely and asks you to get out or wait.
There are _many_ people who cannot or will not driver. They won't just take over control of a vehicle they're unfamiliar with. Teenagers, the elderly, people without a driver's license, people injured, ...
I guess what I’m trying to say is that it’s very difficult to imagine that if AVs take over let’s say over the next 30 years that the end result will still be running on the same infrastructure we rely on today and that if we will still be a society where most people drive most of the time that AVs will really be all that transformative in the first place since they would be filling a sizeable but still relatively small use case- taking a cab around a major city. I can’t tell whether it’s the amazement of seeing a driverless vehicle or the actual utility of it that generates the excitement
They'll do what we've been so-well-trained-for at self-checkouts: the passenger might be given control of the vehicle in such situations (e.g. loss of network connection).
>within 5 years
As for predicting the future: I think within five years ALL vehicles on public roadways will require a beacon for travel, simply to alert other self-driven vehicles & intersection controllers. This process will be gradual, akin to "insurance discounts" for allowing driving habit monitoring (e.g. without a beacon, traffic lights won't auto-cycle for you).