I often post anonymously on Wikipedia. As far as I know, Wikipedia neither formally nor informally discourages anonymity. I'm sure I've been responsible for my share of drivel, and (I hope) for my share of insight.
I believe that what people (including myself) have to say is more important than who happens to be saying it.
(2+3=5 is true whether said by Gandhi or Hitler, 2+3=7 false likewise.)