Yup, people who are seriously politically active in online venues are disproportionately likely to be using nicknames, and this can only become more likely if they aim to actually run for office. This is one key reason why anonymity/pseudonymity is seen as an important free-speech issue. And sites like Facebook, which try to enforce the use of real names, are widely distrusted as places for some political discussions, for much the same reason.

(Of course all of this is very much context dependent. A Real Names policy will benefit other political contexts, which are less related to the roughness of deliberating and negotiating about political ideas, and more about things like expressing support for firmly established proposals by publicly taking a stand about them. You can see this very clearly with "Neoreaction" at its current stage - how many people would be willing to sign their name under a petition asking for a king to rule them, and for "shares" of the country to be distributed to a new aristocracy?)