Besides the obvious privacy concern: at the very least in my state (Illinois), it's not lawful for public bodies to disclose the license plate numbers read from ALPR cameras, so this data set is necessarily incomplete.
But, give it a year or two, and you can replace this whole website with a black background and 72 point white bold text "YES".
There is already case law that makes the records collected by government through these methods no different than any other public records, especially since they are publicly visible license plate numbers.
That has its own problems because it shields/deflects from the bigger issue of being treasonous, i.e., grotesque violation of the law of the Constitution, through mass surveillance that has also already been abused for various kinds of criminal acts by law enforcement.
Flock is a private company, right. That's the whole schtick. Like, Flock can retain records indefinitely for example, they may sell those records to the government but they're a private party.
Rule 1. Do not comply in advance. Do not accept it as inevitable. Do not give away your power without friction.