Feminism is about empowering women to make their own choices. This should include the choice of clothing and whether or not to wear it. Ms. Ratajkowski has every right to pose nude for a photo shoot, and it makes a positive feminist statement that is both comfortable with her body, and is able to make choices about what to do with her body.
While I'm sure a good argument can be made against over-sexualization, I believe that Ms. Ratajkowski has every right as a woman and a feminist do whatever she chooses with her own body. In that light, I believe that criticizing her for posing nude is in its own way, a form of sexism.
This seems like a way for her to get attention, but not to make a statement that actually advances the movement of feminism. Emily's actions do nothing to advance the idea that men and women should be equal, as all she did was pose without her clothes. This is not a feminist statement.
Emily Ratejowski posing naked to make a statement got a lot of attention. However, most of the attention it garnered focused on Ratajkowski posing nude. Many that saw her naked picture are more interested in it then the statement she was trying to make. In short, posing naked is not an effective way for most feminist to make a statement.