If what you have to say isn't worth your reputation, then maybe you should think twice before spreading that same thought to real [and often vulnerable] people on the still-nascent internet.
Anonymity, and even pseudo anonymity, ensures free discourse.
Good ideas, no matter how unpopular, scary, or threatening to a power structure that could crush the commenter, rise to the top of most conversation formats with reliable regularity.
Yeah, it consisted of people with mental faculties that far exceed the minimum requirements of today's internet.
Because I believe the current trajectory of society will place more than just my reputation at risk for expressing my thoughts. Make of that what you will.
Though sadly, the truth seems to benefit most when it is backed by the real or proverbial blood of martyrs.