Given a model is given a complete set of human data, there should be equal amounts of leaning in all directions.

This assumes that humans are equally likely to lean in all directions, which is a false assumption. Voices are present as much as they are socially permissible. Voices are unequally represented depending on access. Some voices are absent because historically they were suppressed or persecuted. Even if it was a perfect data set of all human voices that ever existed, it would reflect the societies we create and the behavior we select for.