> I thought the point of online anonymity was that it allows people to be judged based on what they say and do, not by their name, nationality, certifications, or whatever.

I agree, in general, and you provided a nice argument in support of your position. Sometimes, however, you can’t help but express a strong opinion and nothing else, as I did above. Then your post shouldn’t be anonymous. Another example is when you give advice, such as in "Ask HN". Then the reader would certainly like to know your background.