Exactly. If men could get pregnant, they’d be women.
I do sometimes wonder about the sexual behavior of a hemaphroditic species. Because even if you can produce both male and female gametes most such species just put as much energy into both types, and the issue sorts itself out because reproduction just means dumping your gametes into the water and hoping for the best.
But suppose you have placental mammal style internal gestation of the embryo. That means acting as a female has higher costs than acting as a male. So when two individuals come together to mate, they could both act as females, or one could decide to only act as a male, to preserve their options. So I imagine every sexual encounter is like a wrestling match, with each individual trying to force the other into the female role, while trying to avoid the female role themselves. Imagine all the male-male combat for mating privileges that animals do, only at the end the winner rapes the loser. And that’s a pretty disturbing mental image, and I’m sure there’s plenty of gay porn with that storyline.
Anyway, the end result of this sort of evolution is that if you’re an obligate male you never have to pay the penalty of gestating the young, and so the setup isn’t evolutionarily stable. Obligate male cheaters ruin things for everyone. Except if everyone tries to be a male that makes the advantages to being female greater and greater, and so you have the typical 50-50 sex ratios common to most species.