RE: In 2015 which gender is more oppressed?

While probably not what you were thinking of, I’d say the gender identities lumped together under the umbrella of “transgender” would be the most oppressed. Even if you don’t count trans-women and trans-men as separate genders from female and male (and I’m not sure you should), certainly any of the “non-binary” gender types are at a disadvantage, given that people are often not even aware of there being more than two genders.