I see your point - but the song was never meant to mock women for being extra feminine or embracing their sexuality. It's more of a "Don't change who you are because men expect you to" kind of message. The mid '00s were a crazy time and representations in the media were not nearly as diverse as they are now. Tabloids and TV were enforcing the idea that young, skinny women with long, blonde hair were the only ones who deserve any spotlight and most of the time, they were portrayed in a way that they needed to be super sexual to get the attention from the guy. And trying to imitate what they were shown, many kids gave up on their actual interests, starved their bodies and acted more sexual than what they felt comfortable with to not get rejected.
So that's where the song is coming from. It's not about shaming girls for choosing barbies because 'being girly is so bad'. It's about the toxic way female celebrities had to present themselves in order to have a career. And how girls started to think they had to throw away their true nature just to become objectified by some guy.
If you want to look into it, there's an interview she did with Oprah where they talk about the meaning of the song. It's pretty insightful but I'm sure she'd do things a lot different now. The MV's visuals were provocative enough to spark a discussion... but it did what it had to do and after not having performed it in 15 years or so, it appears that she has left in the past where it belongs