I've had this going through my head for a while, but I couldn't quite articulate why I had this feeling that it shouldn't be taken at face value.
I think I worked it out. Women's groups are worried that their privileges will be on the chopping block and rolled out the most absurd thing they could in a desperate attempt to rally people behind defending them, on the day where everyone thinks about the most and usually only positive female influence they have in their lives.
It's a cheap trick, the typical appeal to emotion that they're so famous for. You're thinking of the woman that likely you have a deep connection to, so you think "I don't want her to be called a birthing person, she's my mother" and back whatever retarded bullshit Defending Female Privilege Bill 42069 contains.