> If I wouldn't do something in public, I wouldn't post it to social media. Maybe I'm unique in being able to restrain myself.

Another possibility occurs to me: you are on a path in your life where, for whatever reason, you rarely engage politically with the world. Or at least you rarely engage politically in a way that would bring a substantial risk to your career, personal, or political life. Or you are lucky enough to be in a situation where you don't have to do that in order to protect yourself.

I'm not implying that you do this consciously (though that is a possibility). It may be something like the mathematician who finds a job at the NSA that fits their interests like a glove and burrows away their for the rest of their life. There is certainly nothing wrong with that, just as there is nothing wrong with the person who just "clicks" with adversarial political action their whole adult life.

However, while I'm not particularly political myself it takes me maybe 3 seconds to imagine people who are (esp. people affected by Trump administrations policy toward immigration). So I'm left confused by your apparent inability to do the same. I am certainly not unique in being able to empathize with people who's safety is at risk from Facebook's creepy, leaky, sniff-it-all system of social media.