Wishing for equality for all is just part of being awake to religious biases against any type of person. Wishing for equality for all also addresses bias against religious peoples of all kinds. If many western feminists seem to detest Christianity, then read The Old Testament--there are thousands of references and instructions stating again and again the idea that men have dominion over women & more spiritual capacity than women--and more worth in the eyes of God. Christianity is no different from Islam traditionally in that women's rights are subdued over centuries of behavior that is reinforced and reproduced to this day in the majority of churches where male leadership is predominant at nearly all times, within and outside of the church. There is no preference for Islam but western women must address the influence of the majority religion in their own nations every day.
When it comes to feminists being aware of inequality and feeling vulnerable to the majority of western males and their feelings of entitlement, they also see that many of those men who feel entitled are remaining in power due to Christianity. Those same men who feel entitled are often also deriding and attacking Islam and Islamic peoples (hundreds of millions of Muslims of all kinds and cultures exist all over the world) with impunity. When people like feminists see that kind of unfairness rearing its filthy head, they see that as a continuation of their own fights for respect for all individuals regardless of differences.
People who have rigorous thought processes, as many feminists do, are able to address unfairness but still support that rights of all who live on Earth to worship as they please. If women of western nations expect more equality from their dominant culture, they are challenging what is at hand and trying to reform it. That doesn't mean they hate Christianity. It means they expect more from it. Churches and the people who operate them are not God. They are fallible human beings in power who often have too much power to abuse.