I think you're both a bit off here to be honest.
Sex, just like fast food, television, any other diversion, is objectively a waste of time; or at very least an unproductive use of it when not intended for procreation. (I'm not preaching austerity here, not saying it's shameful or bad)
Additionally, the traditional family unit is on the decline of course and while I disagree with the anti-lgbt sentiment(among others) below this is a conversation that we need to be able to have as a society.
Demonstrably children in a single parent household have lower success rates academically and are at much higher risk for a variety of mental disorders.
Also demonstrably men and women who have had more sexual partners have higher rates of divorce and(of course) also lower marriage rates.
Historically we've evolved under the constraints of long-term single partner relationships in a stable home as the foundation for raising a child. We're changing that a lot, very fast on an evolutionary scale, I do think there are productivity and general well-being concerns about raising the next and current generation that should be talked about.
Anyway, this is all largely an aside; I think male contraceptives are a good thing, but I likely won't partake myself nor would I have my child do so unless he wanted to of his own volition.
Edit: By the way, I think you're a bit off because you've completely brushed his statement aside as esoteric and irrational, many people really do feel that way about sex/relationships and their opinion is just as valid as yours. I think he's a bit off for a few probably obvious things from his follow up.