The argument was, yes it's legal to put a tail on a person when they're out in public because that's just a cop observing a person of interest out in public. But electronic trackers are something quantifiable different due to the ease of tracking many people without having to use manpower to do it. It's the thin-edge of mass, casual surveillance of the population.
In other words, putting a tail on someone should be manpower intensive because that's a check on police power, they have to really want to track someone to invest potentially several officers' time to it full time, whereas sticking a bug on a car is something they can do to dozens of cars per day per officer.
Of course now they don't even have to do that because our police state has normalized centralized cctv camera databases, license plate trackers that continuously track the movement of every vehicle in a city into a database. Now they're doing the same with facial recognition.
Now it's even a felony in Florida to do anything to block license plate trackers from tagging your vehicle (so you can't obscure your plate in a way that leaves it readable to humans but not to the automatic tracking software). No doubt we'll have such laws for facial recognition software soon as well.
Police were always allowed to bug a vehicle with a court order. They weren't allowed to just casually bug random people's cars because that's mass-surveillance. Now mass-surveillance is completely normalized. Every citizen is treated as a potential criminal and surveilled into a database.
A good friend of mine who also works on tech is utterly disconnected from current events. Whenever I offer a discussion or say “hey did you hear about X?” his response is always skepticism that such a thing could occur. He has a newborn and now he’s even more disconnected (somewhat more understandable given the child).
It seems like a lot of people in tech are like that, or increasingly like that. I have a diverse stable of publications, journalists, subject matter current events podcasters, and other sources in my feed readers and my circle. Sitting between these things, it seems like there is a widening gulf.