She is the first woman major party nominee. That already puts her up in the pantheon along with Susan B. Anthony, Gloria Steinem, etc.
She tries too hard.
She wanted to be the first woman nominee so SHE could be the first female nominee.
When you become an icon, you can't try. You just are. Hillary will never be a feminist icon like Susan B. Anthony. She only got to where she was due to her husband. Every step she has made was about her. For example, she ran in the New York Senate race because it was a slam dunk guarantee win for her. She stole the seat from a woman who did work her way up there (Nita Lowey).
She wanted to go down in history as the first female President. If she would've died the second after taking the oath she would have been OK as long as she won. That to me is not what an icon should be all about.