This is not a shariah issue. This is the issue of protecting the rights of women at work, irrespective of religion.
Yes. Men should lower their gaze and they need to be taught how to behave.
But do we honestly think that if given the choice, the female flight attendance would want to make some suggestions on the uniform that they wear every day?
And yes. If they wanted to, they should be give the choice to wear the hijab, as much as a Hindu should be given the choice to put on the Dotti and even for the male Sikh to wear the turban.