Thanks for laying it out. I am curious about identifying logical fallacies. But after your description, strawman is exactly how I read the picture. Here's how it goes in my head: there's an unstated assumption that since circumcision in America is so common, that pro choice people are for it. And then they point out that circumcision at birth is against bodily autonomy. So yeah, strawman.

To me, the fact that it's intended as a joke is besides the point, but still supports strawman. Why is it funny? Because you contrast the pro-choice bodily autonomy ascribed to the pregnant woman with the lack of bodily autonomy for the circumcised child. But this juxtaposition ascribes the decision to circumsize the child to the pro choice person. Meaning, they're claiming that this is those people's opinion. And arguing against it. If instead we said that person A is pro-choice and person B circumcised their child then it isn't funny or clever anymore.