But I don't actually see the purpose for a woman's class.
That's okay. You don't have to attend one.
To paraphrase what I said above: it doesn't matter if you don't see the purpose. I don't see the purpose in all kinds of things, but then, those things don't require my understanding in order to justify their existence. Universal understanding and consensus is not the basis for any endeavor, and why people think a women's aikido class should be some kind of exception to that, I'll never know.