Well, nothing would survive if we didn’t pass it down to our children. The human race wouldn’t survive if humans didn’t procreate.
Of course, but that's not the only point of humans having sex. When 1Cor 7:3 speaks of 'rendering the marital due' it isn't talking about procreation, but based on what the older JW man said I get the impression that's the way JW used to look at it.
The remark the speaker made in the video about "the breeding act" seems out of place. I think he used that kind of language to suggest that masturbation is an animalistic practice and should therefore be repugnant to people. That kind of word manipulation is common for Watchtower.