There are several independent reasons. First, people who need a psychiatrist (or doctor in general) sometimes do a simple background check on them. Like, put t

There are several independent reasons. First, people who need a psychiatrist (or doctor in general) sometimes do a simple background check on them. Like, put their name in Google and try to find some reviews, just to see if other patients were satisfied with them or not. Some topics that Scott debates would be quite inappropriate for people seeking psychiatric help. For example, imagine that you are suffering from paranoia, and you find out that your psychiatrist seriously considers the possibility that superintelligent robots may soon exterminate the humankind. Second, although Scott is generally left-wing, he is not fully 100% on the side of the left-wing orthodoxy. For example, he would write an article about how Trump is a horrible person and a disaster for America, but would also mention that a few details that the mainstream media said about him were factually incorrect. For some people, anything less than 100% compliance is unacceptable. (Often heretics are more triggering than full enemies, because the enemies at least fit into the black-and-white picture, while the heretic ruins it.) Third, in the discussions below the articles, multiple political opinions are allowed. Again, this is quite triggering for some people, because according to their logic, why would you allow anyone to express their opinion on your website, unless you actually agree with them? Of course, this is reported selectively, like "did you know there are fans of reactionary politics on SSC?!" without mentioning that they are debating there with e.g. hardcore stalinists, and that both sides are just a small minority in the mostly moderate audience. The second and third point are why some people are so eager to expose Scott's identity, and the first point is why he tries to prevent it.