I'm a little confused by this article. It is facially opposed to extrajudicial blacklists, which, sure, I'm 100% on board with. Those are civil rights violation

I'm a little confused by this article. It is facially opposed to extrajudicial blacklists, which, sure, I'm 100% on board with. Those are civil rights violations. But it seems to spend most of its time and evidence on what seem to me to be totally fine surveillance. It's not a 4th amendment violation for a police officer to be in a public place and pay attention to the public movements of suspects. You don't need a search warrant to write down "so and so went to the bathroom" You don't even need any police powers. I'm pretty sure any random person could make a log of what they can see someone on an airplane they were on did during the flight. What abuse of power is supposed to be involved here?