Yes, people are saying this. Search any major social media site. Or Google the phrase for any number of articles about the rise of this and other similar sentiments online and irl.
Fediverse is hardly keeping up. It's already a trend. That's why I'm still on X (and I hate to do that), where all of it is shown in realtime. There are already elementary school boys spouting that stuff to their female classmates. Read a tweet from a teacher who cheered a girl that snapped and knocked a boy out after he said it.
The phrase “your body, my choice” appears to have made its way offline, specifically into schools. Young girls and parents have used social media to share instances of offline harassment. They include the phrase being directed at them within schools or chanted by young boys in classes.
On Facebook, the phrase “your body, my choice” is currently trending, with 52,000 posts in the last 24 hours. One parent stated: “Today my daughter was told three separate times on campus ‘your body, MY choice.’ The third group of boys told her to ‘sleep with one eye open tonight.’”
Is a 52k trending post not sufficient to qualify as a slogan? That's more pull than most marketing campaigns actually achieve.
If anything, little (and not so little, the incidents are being reported on campus) shits using it is worse, because it's a pretty good reflection of where the next generation is headed.
I assume it's ultimately serious (they want to drop the pretense that it's about the value of the life of a fetus) but a use of irony poisoning on some level. Some real zero self awareness assholes regardless.