Do you worry about some random asshole kid hurling a re-bar in to rush hour traffic? REing automotive tech, setting up transmitters, and spoofing traffic data to throw a virtual re-bar in to rush hour traffic could become a pandemic unless we figure out a way to fight such attacks.
The difference between these two scenarios is that the asshole kid throwing rebar is easily detectable and to do it has to be at the location of the crime.
The asshole spoofing traffic data, depending on how the transmitters are set up could potentially do it from a long distance away, and may actually be hard to detect.
Emergency vehicles in some cities can emit a signal that changes lights from red to green. It's a felony to spoof those devices, but people still get caught doing it.
I'm sure a system can be made resilient to a single bad actor, but, yes, those attack vectors will have to be thought through.
