The obvious problem is... it's not possible to ask someone whether they would like to be conceived prior to conception.
Agreed, but how do you go from that to "therefore it's fine to conceive"?
If someone at a party is passed out and therefore it's not possible to communicate with them, we assume they don't consent to anything. Why doesn't the same reasoning apply here?
That's fine, but there's no rational basis for your position, and therefore no reason to call the dude "stupid" regarding that. He thinks life sucks and you don't but that's just a difference in values.