So feminism assumes that it is due to society that women can become pregnant and men can't?

If men could get pregnant, they would already have invented a machine that would do the pregnancy for them. Or at least trying to invent such machine would be a high priority. But because it's a "women's job", no one cares.

Yeah, now give me some mansplaining about why machine pregnancy would be "against the nature" (just like homosexuality, or votes for women), but sitting all the day by the computer is a natural order or things.

So while originally it was a matter of biology, it is a social decision to keep things the same way in the 21st century. Check your privilege!

(Not completely serious, just trying to impersonate a feminist.)