The algorithmic loneliness behind falling birth rates

With few exceptions, birth rates are falling all over the world, a trend we can no longer explain by housing costs, unstable employment prospects, young people staying at home longer or gender inequality. All of these matter, of course. At the same time, as an article in the Financial Times, "Why birth rates are falling everywhere all at once", points out, where the smartphone and social networks became the default environment for meeting our future partner, fewer people are forming stable relationships, with the concomitant negative impact on the birth rate.

I've long been concerned about the polarizing effect of social networks. Their algorithms learned that outrage engaged people, that conflict generated more clicks than nuance, and that locking each user in an echo chamber was much more profitable than exposing them to a plural reality. It wasn't an accident: it was by design. Britain's Royal Society warned back in 2022 that the problem of disinformation could not be solved simply by removing content, and instead required attacking the ways that misinformation is spread. In other words: the problem is not only the lie, but the architecture that rewards it.

We're now beginning to see that this architecture not only warps the public conversation. It also distorts private life. A recent paper by the University of Cincinnati's Nathan Hudson and Hernan Moscoso-Boedo, "The collapse of teen fertility in the digital era", links the expansion of smartphones, mobile broadband and 4G with an abrupt drop in adolescent fertility, accompanied by a very sharp reduction in face-to-face socialization and a shift towards digital leisure. This not moralizing about phones, but understanding something much more uncomfortable: when a technology captures the social time of a generation, it also captures the conditions in which relationships are formed.

Social media promised us connection and gave us substitutes for connection. It gave us likes, followers, notifications, messages, stories and reels, while narrowing the spaces where people find themselves unscripted, unfiltered, without permanent comparison, and without being competing against an optimized version of everyone else. To find a partner you have to expose yourself to imperfection, to clumsy conversation, to physical presence, to shared boredom, to vulnerability. Platforms, on the other hand, have turned social life into an infinite showcase in which everyone seems more attractive, more interesting, more successful or happier than they really are.

That has consequences. If sentimental expectations are formed by looking at Instagram or TikTok, they are formed against a manipulated reality. If free time is consumed by doom scrolling, the time needed to get to know others disappears. If the social bond is transformed into a permanent comparison, the real relationship always seems insufficient. And if the algorithm learns that insecurity, anxiety, desire and outrage hold the user back longer so that they distill more information and can be served with more ads, then the company has a direct incentive to manufacture psychologically toxic environments. The problem is not that young people do not want to have children: it is that fewer young people are able to build stable relationships.

The demographic evidence points in that direction. In 2024, The Lancet documented the global fall in fertility and its enormous social, economic and geopolitical implications. The Financial Times article mentioned above goes a step further: in many countries, the problem is no longer that couples have fewer children, but that there are fewer couples. That is a fundamental difference. Traditional public policies such as parental leave, childcare and tax benefits can help those who already have a family project, but are of little use if a growing part of the population is isolated, frustrated, trapped in dynamics of comparison, emotional precariousness and relationships that are increasingly difficult to initiate and sustain.

The result is more loneliness. The US health authorities are already talking about an epidemic with profound effects on health and well-being, warning that we cannot conclude that social networks are safe enough for children and adolescents, with significant indications of risk to their mental health. This isn't technophobia, it's about responsibility. No industry should be able to target minors, or anybody else for that matter, with addictive products, optimized through mass experimentation, without first providing evidence that they aren't harmful.

Of course, social media bosses hide behind the alibi that they are giving people what they want. This is false. They don't give us what we want, they give us what maximizes permanence on their platforms. They're not optimized for well-being, knowledge, friendship, love or community life, and instead are finely tuned to maximize usage time, recurrence, reaction, and ad monetization. If to achieve this they have to publish extreme content, they do so. If they have to turn self-esteem into a dependency mechanism, they do so. And if the aggregate result is a society that is more lonely, angrier, more distrustful and with fewer stable relationships, these are simply externalities, collateral damage, if you like.

Therein lies the central negligence: social media have designed systems that intervened in human behavior on a planetary scale without assuming any responsibility for their effects. First they broke off the public conversation. Then they broke trust. Now we are beginning to suspect that they are also eroding the basic conditions of social reproduction. Not because Facebook, Instagram, TikTok or YouTube alone "cause" the fall in the birth rate, but because they amplify, accelerate and consolidate all the factors that make it more likely: isolation, insecurity, unrealistic expectations, polarization between men and women, anxiety, deterioration of mental health and replacement of face-to-face interaction with algorithmic consumption.

It is not a question of asking people to have children: that decision belongs to each person and each couple. This goes much deeper: asking ourselves what kind of social environment we're building when the dominant infrastructure of relationships between people is designed by companies that earn more the longer we spend staring at a screen. A society in which conversation deteriorates, trust erodes, intimacy is deferred, and the partner becomes statistically less likely is a society that has delegated too much to algorithms that were never designed to take care of it.

The solution is not to ban the internet or to idealize a past that did not exist either: it is to prohibit hyper-segmented advertising, regulate recommendation systems, limit addictive patterns, demand real transparency, stop the exploitation of minors, deactivate the automatic spread of harmful content and rebuild spaces for face-to-face socialization. It also means ceasing to accept the absurd idea that innovation consists of launching products into the world and then studying the damage. Innovation without responsibility is not progress: it is extraction.

I have been saying for years that social networks are eroding our democracy and undermining the shared truths our societies are built on. Now we are beginning to understand that perhaps they are also destroying something deeper: the ability of a generation to meet, bond, trust and build a life together. And when a technology begins to affect not only what we think, but how we live, love and reproduce, continuing to talk about "engagement" is practically obscene.

(En español, aquí)