I'm going to say it again for the cheap seats.
Men determine what is beautiful in women.
Just as it is women that determine what is "hot" or "sexy" in men.
The key issue seems to be that men accept this binary reality whereas women (primarily in the form of reality denying feminists) don't. They wish to change it.
My counter-argument is simple:
You see, barring the 1-3% of the non-straight population, it effectively is a binary relationship men and women have. And "beauty" or "attractiveness" is ultimately determined by the opposite sex.
You can lie to yourself and tell yourself that all women are "beautiful" but you are merely changing the definition of "beauty" to fit your definition which requires less rigor, effort, self-control, and discipline. In order to be beautiful you need to be appealing, by definition, to the opposite sex.
But perhaps we could approach it from another way. Think of the word, "attractive." Well that implies "attraction" which means there are two entities involved. You are attracted to one person, just as another person is attracted to you. It's implication is damn well near the law of gravity that two bodies will have a gravitational, or in human's case, sexual pull towards one another. Ergo, to claim you don't need anybody else to think you're attractive of beautiful, that you on your own little lonesome are "beautiful merely because you exist," implies there are no other entities providing a gravitational or "sexual" pull.
Which only means one thing:
You're a metaphorical sexual black hole collapsing on itself and only attracted towards itself.
A description most apt to most feminists.
(oh, I'm sorry, was all that physics and math talk above most Masters in Women's Studies' heads?)