Earlier quoted context omitted.
a police officer observing you briefly with their eyes is quite different than an entire police department outsourcing surveillance of protected activities to a third party which monitors your online activity over time.
How? What expectation of privacy do you have walking down the street, or in your public social media posts?
I've learned that when people refer to "constitutional rights/protections" outside of a strict legal setting and framework, it's almost always disappointingly predictable and devoid of merit. The gulf between the law as its written and interpreted through the courts, and what people with a casual interest believe it to be, is really impressively vast.
At the end of the day if you want privacy, don't broadcast your activities on open platforms that were DESIGNED to observer and record you.