I think you missed the part about the US government not requiring an ID for copyrights.
To assign copyrights, however, does require a legal name or a pseudonym widely known to be associated with a known real name.
Also, if you want to move to the topic of contracts (such as one giving copyright for code to Gentoo), there are plenty of perfectly valid ones that can be accepted by clicking or selecting "I Accept". No name, signature, or ID needed.
I'd question the legality of any "contract" lacking something to satisfy the requirements of the E-Sign Act, which are a little vague.
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