We wear a hijab to keep modest and so the public eye van refrain from staaring, but wearing the hijab gives out even more attention. Doesn't that defeat its purpose? JazakAllah.
The commandment for doing purdah and being modest is for both men and women. They are both told to lower their gazes. Whether or not women are doing purdah, men will always have the natural urge to look at women. That is why they are told to lower their gaze. The purdah grants additional protection for women as those who do look are not given incentive to "stare" further. Furthermore, the hijab may cause non-Muslims to stare out of curiosity. It's not sexualized.