Bitcoin for example, uses pseudonyms... not anonymity. A pen name or a hn username is a pseudonym. A voting system needs to be anonymous not pseudo-anonymous^, by using a pseudonym. If each voter had a secret number that is attached to each vote, that is a pseudonym.
"L is 32 years old. She works as a nurse in Moscow." - L is a pseudonym. It isn't anonymous even though the name is ommitted.
^This can get grey, as even a piece of paper with an X on it will carry certain metadata or related data: which voting booth, etc. But, the goal is anonymity. IE, the X cannot be tied to anything else.