Yes, I know the women were overtly sexualized in the Original Series. However, if I'm not mistaken, the outfits were a concession to the network, and in the original pilot (The Cage), the women were dressed in pants that were the same as those worn by the men. Gene Roddenberry had no choice but to "sex up" the women if he wanted his series aired. Even still, by the standards of the time, the Original Series was quite groundbreaking in its treatment of women (Uhura on the bridge, for instance), and in the movies the women wore the same uniforms as men.
He aspired to a world of gender equality, and later incarnations of the franchise should have taken that further and made good on the ability to do what he could not, instead of selectively confining themselves to the boundaries set by 60's network executives whenever convenient.