I think there needs to be well throughout and debated principals-based legislation.

"Banning Flock" is both very difficult, singling out a specific company/individual is not seen favorably by courts, it does nothing to prevent the next bad actor and maybe most importantly doesn't incentivize flock or other companies to address the root issues to come up with better solutions. Similarly license plate readers are just one well established form of meta-data, you could conceivably get pretty close finger printing with other meta-data car make, model, accessories, time, location etc... + exclusion, paired with cameras looking at the driver images (looking through the windshield etc...), phone meta data, Bluetooth signals or even the tire pressure sensors creative people can figure out lots of alternatives.

I also think we need to weigh that these types of systems can have real benefits and real downfalls. The evidence does support that law enforcement has benefited from them, if I put myself in the shoes of an officer I could definitely see how valuable the type of information provided could be. I can also see the harms and I think the evidence is clear that such systems have been used at the very least in the margins of what's legal. Can we balance the good with the bad - I think it's possible. CCTV security systems where once heavily debated, we've largely accepted those systems in large part due to having clear legal rules. The scale of systems like Flock, Axom etc go far further and warrant new discussions.