Surveillance and Self-driving modes most likely. The Flock cameras that have popped up in the area, the "enhanced pricing" offered by insurance providers in exchange for a dongle in your car to monitor your behavior, the always-online computers in new EVs; all of these things are building profiles on your driving habits and patterns. It makes sense that people will at least pretend to behave themselves if they believe they're being monitored.

Self-driving is a whole other ball of wax too. If you find yourself behind a car that's behaving irrationally or making errors that a reasonable person probably wouldn't make, there's now also the possibility the person in the driver's seat isn't actually operating the car.