We spend more time online. We socialise less. Our mental health is getting worse. These three trends have been obvious for some time – particularly among the young – but now more evidence is linking them, and alarm bells are sounding louder. This is a crisis, and we will need to solve it. What, exactly, has happened to hanging out?

Much has been written on the idea that hanging out has been displaced: glued to our phones, some social needs thereby fulfilled, we have less time to see our friends in real life. But this misses, I think, a parallel cultural shift. Hanging out has not just been displaced but devalued. We think it less important, less prestigious. This is profoundly odd, for a social animal, but we seem to have entered an era in which real-life socialising has dropped sharply in status. It has lost its social cachet.

This is true even among the people we used to call “socialites” or “it girls” in what used to be “the party scene” – the sort of demonstrative socialising that stamped your place in a celebrity hierarchy. The value of being seen with other famous people, in a particular place, at a particular party, has fallen.

You can trace this in the decline of the gossip column and the “bystander” magazine photo spread. You can see it also in the online profiles of celebrities, who prefer to show themselves alone, at home, the better to engage intimately with their fans. (Florence Pugh, for example, has a cosy cooking YouTube channel, filmed from her kitchen). Once it was high status to go out; that was where you promoted yourself, and stayed relevant. Now celebrities seem to worry it looks try-hard, or unrelatable. There is no shame in staying in.

It is true, too, for the rest of us, particularly teenagers and generation Z. It has become fashionable for young people to describe themselves as introverts who find parties “stressful” and suffer from social anxiety. A recurrent theme on Instagram and X is the joy of cancelled plans, and being overwhelmed by run-of-the-mill situations such as running into your neighbours. People film themselves alone in their bedrooms on a Friday or Saturday night. I’m old enough to remember when this sort of thing would brand you as a loser. Now it’s the extrovert who looks like the odd one out.

Mark the speed of the shift. It was only in 2012 that Susan Cain felt moved to write a defence of the introvert in her book Quiet. Society, she wrote, saw introversion as “a second-class personality trait, somewhere between a disappointment and a pathology”, and was held in thrall to an “extrovert Ideal – the omnipresent belief that the ideal self is gregarious, alpha and comfortable in the spotlight”. Well, not any more: in an online world built by nerds, the jock is going out of fashion.

The change is documented in the archives of social media. The early days of Facebook were primarily about recording (and showing off) your offline social life. People used it to post pictures of themselves with their friends, and at parties. If there was cachet to be had, it was in looking like you had lots of mates. But that has changed. Now, in 2024, young people rarely post evidence of gatherings. Influencers appear in videos alone. It is OK to be antisocial, to be socially anxious, to hate parties, to spend more time with your pets than with other people. Actually, it is more than OK – in a world where relatability is currency, it reads as relatable.

This is of course, in one sense, very nice. For introverts, the world has become a more accepting place. Social judgment is always unpleasant, and part of the great good the internet has done is to create friendly spaces for people who have not always had it easy offline. But there are other consequences of doing away with the seemingly oppressive idea that people “should” be out there, hanging out with their friends, in order to seem cool.

The social pressure that once drove people, particularly teenagers, out of their bedrooms and into the lives of others has slackened and dissolved. Without that push, apparently, society slumps on its bed, scrolling. The social pressure has also been displaced. Social status is something the internet is teaching young people to quantify – in “likes” and followers. Online, social lives are rendered as data, points to accumulate. Simply spending time with friends doesn’t create social “value” in the way we have learned to think of it – as something we can measure and hoard. In an online world that values the production of content, hanging out with friends is a profoundly unproductive thing to do.

How can we push against this tide? In her book Hanging Out, Sheila Liming argues for a transformation in how we view spending unstructured time with friends – we need to see it as valuable again. But I wonder, as the internet whirrs away, rewiring our brains, if this will be much harder than it seems.

• Martha Gill is an Observer columnist