As usual, I think the most important determinant in a child's eventual maturation is his/her parents.
For example, my sister and I were certainly brought up watching Cinderella, etc. She grew up to be a passive, spoiled, "princess" incapable of taking care of herself and literally expected a man to rescue her from the drudgery of real life (like, say, a job). I grew up to be a fairly assertive person who relies pretty much on myself. Difference? How we were raised.
I essentially raised myself from the age of 5, with the aid of grandparents and some wonderful teachers who gave a crap. She was spoiled rotten by my parents from the moment she was born and they bailed her out of
every difficulty in life. (My father once drove 8 hours to change her tire when she was 25 years old. And she had
AAA!) She became a passive 'princess' because that is what my parents trained her to be. (Let me note: This is a truth my parents acknowledged as a huge mistake when my sister was about 30 and they realized what kind of person my sister was. I should also add, that she finally grew up when my parents died and she had no other choice.)
Watching movies and dressing up no more makes a girl a princess/porn star, than watching Star Wars and dressing up like Chewbacca turns a boy into an overgrown dog. I loved Barbie when I was a kid -- I never thought I should have a body like hers; for crying out loud at 7 years old I knew Barbie was a doll, not real!
Movies and toys simply do not have as much power as this so-called expert gives to them. Parents have the most power, followed by peer groups. If she's concerned about girl's body image -- which, I agree, is a critical issue in our society today -- then her energy would be better directed toward encouraging parenting that teaches healthy eating and exercise habits. It's far worse to have a father telling his daughters that they're growing up to be fat and no guy will ever want them when their skinny selves reach for an extra breadstick than by watching Snow White. It's far worse to allow your daughter to hang out with girls who have body image problems than to allow her to watch Pocahontas. It's far worse to have a boy watch his father abuse his mother than to watch a movie. Kids can separate reality from fiction and what they usually mimic is reality. So if parents want a certain reality for their kids, then that is the reality they need to model. Or as the old saying goes, "Kids learn what they
live."
) to stuff themselves full of candy and "be" someone else for an evening. 
) Every one was paranoid that we were giving girls the wrong idea with Barbies perfect figure, waiting for Ken to show up, etc, etc. Little girls love to play dress up, always have.
Gimme Jasmine and Alladin any day.
Though if the newly single Prince Williiam came knocking on my door tomorrow, I might just change my mind. 
