I'm not intimately familiar with all the different strains of antinatalism, but I think that's kinda the point? an antinatalist would not consider funding existing people's retirements or possibly even the survival of the species to be sufficient justification for creating new conscious beings who cannot consent to their creation.
Seeing as a big chuck of what someone believes is culturally inherited from their parents, and thus hypothesizing that meme* survival partially follows parent-child relationships, I'd say that that's a problem that will end up self-correcting :)
* In the original Richard Dawkins sense, not in the funny gif sense.
Amusingly we have a case study for this: the Shakers.
"They practice a celibate and communal lifestyle, pacifism, uniform charismatic worship, and their model of equality of the sexes, which they institutionalized in their society in the 1780s."