By choosing to respond to 'your body, my choice' you're also validating it as a statement that needs discussion or response. It doesn't need either. It's a bizarre statement that's meant to provoke. If you don't like the polarization that's happening, don't let yourself be provoked, don't engage, ignore unworthy nonsense. Responding with hatred, however well deserved you think it is, does not help us transcend polarization, it's just another step in the polarization dance.
Not sure I'm 100% convinced of the above sentiment, ignoring it could make things worse too, hatred does sometimes need rebuttal and just ignoring it could be dangerous too. Still I'm wondering if this would be the right approach. I think perhaps it would help if we would not let ourselves be provoked, take a deep breath, and respond in a matter of fact way, that's not snarky, that's devoid of any sense of hatred, that's not exciting, perhaps even boring but honest and true.
I take issue with "it doesn't need either [discussion or response]". There is a real possibility that people will use (or are already using) "your body, my choice" with malicious intent. If that's the case, I will not stand by and do nothing. A knee to the groin seems a good option to me.