Was always suspicious of these.
"A team of security researchers managed to gain “super administrative access” into Reviver, the company behind California’s new digital license plates which launched last year. That access allowed them to track the physical GPS location of all Reviver customers and change a section of text at the bottom of the license plate designed for personalized messages to whatever they wished, according to a blog post from the researchers."
https://www.vice.com/en/article/wxn9...e-gps-location