Technically true

Super true. You can find all sorts of videos online if you e never encounters such a thing. And even in a non sexual capacity “jackass” types often request to be hit on the balls, often repeatedly. There’s also the fact to consider that being hit in the nuts has little or no positive side save perhaps for endorphin release. Preganancy comes with endorphins and all types of hormonal changes, and based on the individual woman there are some things they may like about pregnancy and the feeling of or certain stages of- and at the end of which they create a life. Humans are evolutionarily (or divinely of one prefers) wired to want to make babies. Our reproductive drive tends to override almost all other drives and concerns in most humans natures. So yes- I’d disagree with the statement not just that men don’t ask to be hit in the balls, but on the grounds that pain and endorphins aren’t the only results of pregnancy.

A wonderful scientific notion. It would however not answer the debate as we would need a significantly sized sample group to help diminish the subjectivity of pain between people (even among biologically born female sexed people there is not a concensus how much child birth hurts, and some women say it is relatively painless for them. Even the same woman may have different responses by birth order, such as each baby being easier or harder than the last, or say 1=easy 2=very hard 3=easy, etc.) There’s also the fact that we don’t have a conclusive proof that there would t be differences in tolerance to pain either based upon gender or brain chemistry from neiropathwau formations prior to the change. So I do think there would be merit on your method and praise the cleverness of the proposition, I do t think it could accurately decide or ever really indicate in a non subjective way which hurt more. If I had to guess though I’d say childbirth hurts more as an average.