I interpreted "roughly speaking" as wanting to skip over the obvious mechanical details like you mention and instead focus on the cultural norms affecting why G

I interpreted "roughly speaking" as wanting to skip over the obvious mechanical details like you mention and instead focus on the cultural norms affecting why Gen Z doesn't want children compared to previous generations. bell-cot's comment is well aligned with https://www.thetimes.co.uk/article/young-put-off-having-children-by-global-fears-z5c2w5f3l https://www.thetimes.co.uk/article/young-put-off-having-chil... which is one of the cited sources. It starts "Only half of Generation Z and millennials plan to start a family as finances and global anxieties put them off having children, a survey found." > If all of your requirements were met before people had kids Again, "roughly." Just like we know bell-cot's criteria aren't meant for a subsistence farming society, where the tradeoffs in having children are very different than in a high-technology culture, and just like we know it only make sense in a culture with access to effective birth control and family planning.