who told you that Marilyn Monroe was a symbol of feminism? she had to change her name and entire physical appearance in order to be classed acceptable, her entire life she was treated as a sex object, and even in death her corpse can't get away from creepy old men. she died being ground into powder by the millstone of capitalism
Sie created the Marilyon Monroe persona herself and although she struggled with it all her life, she was far from a naive victim of the circumstances, that belittles her. She was far from stupid, she married Arthur Miller after all.