Men don't need religious beliefs to oppress women, I agree with this, and have experienced this personally. However, many men use religious beliefs to excuse their oppression and abuse of women, saying that this is how god set up the whole thing. A women is not equal to a man in religions where women are expected to be submissive to a man.
It is my own personal view, that the bible reflects the attitudes and culture of the authors, this is why we see women portrayed as less than men. For me it is another indication that the bible is not the word of any god, but the creation of man.