The normal changes that happen in pregnancy are not to ignore. And what about pregnancy through e.g. rape? Do we dismiss the mental harm it would cause to have a daily reminder that someone did that to you?
Stop comparing.
Just say, "i think there should be an opt-out option for men" and move on. You can't compare pregnancy and it's implications with simply parenthood, but you don't need to. Just argue for what you want without punch down. Women are not your enemy. You can have more rights and they can have more rights.