We should concern ourselves far more with content than identity. On the other hand, by prohibiting pseudonyms, we are focusing on them. Why prohibit them at all, if identity doesn't matter? Specifically, by prohibiting them, we are trying to combat the problems of trolling, DramaticIdentity, etc. However, just like passwords give a false sense of security, preventing pseudonyms may really be addressing the wrong problem! Perhaps we should not do so at all, but rather focus specifically on the abuse of pseudonyms. Worthwhile content validates itself; not the name attached to it.
However, one's name lends a degree of personal force that does add meaningful value to a contribution.
However, attaching a name to a personal statement doesn't automatically lend truth to it, nor does it necessarily make validation of that statement any easier.