IMO it really isn't that similar. There's a fundamental difference between a fax machine and Flock Safety. One is a device that you can pick up off the shelf at an office store and which is used by all manner of customers for all manner of things, while the other is a bespoke system designed for and sold to meet public safety use cases.
Furthermore, it's a new evolution of technology. Sometimes quantity has a quality all its own.
It was one thing when tracing a call or tapping a line required a technician to run around the electromechanical switch with a volt meter or a human to listen to your calls 24/7. It's an entirely different thing when it can be done automatically and cheaply at scale.
Before, you could hope to hide in the noise, and unless you were doing something "really bad" (or you had powerful enemies), you probably wouldn't be targeted. We're on the precipice of being technically able to have cheap, total enforcement of most laws.
Should we actually do that though? Will the societal changes be broadly good or bad? That's a question we should be asking, not just jumping in with both feet and pretending that the technology is neutral in the outcome.
For example - the introduction of radios in police cars had a huge impact on public safety and played a huge part in bringing an end to the era of the public enemies. No longer did you just need to outrun the posse chasing you and get out of town for a few weeks until the heat was off. Now you needed to slip out of the dragnet being coordinated over radio around you. That seems like it was probably broadly a good thing ... but even then, it required cost and human risk to accomplish. As we move further into the era of AI policing, we'll leave all of that behind.