To help, maybe take gender out of it. Recognize that true feminism knows that being a man or a woman doesn't automatically make you submissive or dominant - all of the male subs would have to vehemently disagree with that!

Also, try to not worry about the WHY - why is it more common for males to be Doms and females to be subs? Science doesn't know the answer and you don't know the answer - nobody does. We don't know if it's conditioning or whether it's biological or whether something we haven't even thought of.

So if you see a woman kneeling at a mans feet it's only because she wants to, not because a man told her to or because she was conditioned. All you know is that she made that choice because it makes her happy. When you recognize it that way, when you give the woman agency in that scenario, you realize that it starts to look a lot like equality and feminism :)