It's why I'm shocked anyone would even submit this, except to make people angry. There's a reason Unherd articles always get flagged; they very often violate the HN guidelines.
Where did they say this?
Instead of identifying this as a market deficiency, they promote the idea that actually it's a collectivist cause. This isn't true, and it's an attempt to frame pronatalism as a "good versus evil" fight instead of a "cost optimization versus human interests" one. Again, Unherd will blame literally every single possible culprit except the concept of a free market betraying human interests. They deserve what they get, at this point.
That said, I don't like having these kinds of articles on HN either.
You may have skipped past this paragraph:
"Yet radical pro-natalism is only going to grow as motherhood, an ancient political battleground, is electrified by the ever more frightening socioeconomic outlook. Perhaps the only way to make this inevitable tide of pressure and debate work for us is first to recognise it as a collective issue, then to push for a system which does not actively punish women for having children: affordable childcare so that we do not face a career cliff edge; affordable housing so that settling down seems even remotely possible."
Given the very short amount of time between my post and your comment, it's clear you must have written your retort without having read the article.
When you make your next alt account, please don't waste our time with another one of these godforsaken opinion pieces. They are low-quality and so obviously outrage bait, you will have your post flagged before it reaches the frontpage and your account(s) will be banned if you exclusively promote low-quality, single-source material. I guarantee you this is not worth your time.
But it would never be the economy's fault. Raising children is one of the most notoriously cheap American pasttimes! It's uh... gay people's fault! That's right. The gay people did this.