I used to be an avid Instagram user. For a while it generated positive interactions that often bled into real life. A story about a run would be rewarded by a cascade of clap emojis, and maybe a new running buddy. Sourdough tips were exchanged. People love being told that their new haircut is nice. All but the most confident of women are always secretly hungry to be reassured, via the coveted Like or "GORG 🔥" comment, that yes, they are attractive. And they are usually happy to return the favour. There's an unspoken tit-for-tat of dopamine hits on Instagram: I'll throw them at you, as long as you throw them back.
Then I noticed, 3 times in a row, that I had been muting profiles which caused insecurity instead of a desire to connect. 3 times in a row, my scrolling through the feed had put me in a worse emotional state than when I began.
If a potential date or acquaintance makes you feel crappy 3 times in a row, and you are a person with emotionally productive boundaries, you eventually stop making plans and cut them off. I disabled Instagram with the intention of taking a break, and have never turned it back on. I have forgone the upside of potential interactions, but it feels like a net positive for mental health.
Social media is inherently low-dimensional...
... but we evaluate it with the same set of perceptual, cognitive, and emotional machinery that we usually use on high-dimensional data from real-life.
This is true for something as simple as a photograph. Notice that a person can look dramatically better or worse in real life than a photo would initially suggest, based on many things that a photo fails to convey: multiple angles, the way the hold themselves, their mood, tone of voice, lighting, clothes, etc.
A person walking down the street with reasonably healthy self esteem may conclude that they are, say, 70th percentile in terms of attractiveness, intelligence, and success compared to the world at large. (This may be a reasonable and productive delusion, even if untrue. It maximizes the probability that you will put your best self forward in future interactions.)
A person dressed to signal material success may look stressed as they walk past you. A leader with an impressive job title may still err in public. A friend may describe last night's party in a tone which makes it clear that they did not enjoy it very much. It is quite difficult to interact with the real world and draw the conclusion that everything is perfect except you, because there are so many dimensions through which imperfection can leak through. It's easier to patch a static photo than an entire existence.
We lambast newspapers or TV channels for being biased, yet accept the unbalanced character of social media feeds without the same moral condemnation. It's true that no individual friend carries the same power as say, Fox News. But a hundred low-dimensional stories of perfection will combine with crushing weight against the full knowledge of your own life's imperfection. In the face of such skewed evidence it becomes quite easy to draw the (wrong) conclusion that you are the only one who is doing so poorly.
Social media is inherently upward-biased...
...because it is a status game. Status games provide little incentive to share truthful but negative information about yourself.
Not everything is a status game: some interactions demand genuine participation. You still have to show up to work on days when you feel overwhelmed or incompetent. You still have to support your partner on days when you don't feel supportive. The nature of these contracts forces you to interact truthfully, and to bear the full responsibility of your own flaws while doing so.
Participation in social media, on the other hand, is entirely curated. We tend not to share information that we don't think will bolster our carefully constructed social image, even if that social image involves well-intentioned elements of humility and self-deprecation. (Humility is a social virtue, and signaling virtue is still a status game).
You'll see a LinkedIn post from the person who has sent out 100 job applications during COVID and finally succeeded on attempt 101, encouraging others not to give up. But success after tremendous adversity is a widely lauded social narrative, and such a post can be made with a reasonable expectation of support and positive feedback.
You won't hear from the person who is still unemployed, feeling cripplingly lonely, and whose sense of self-esteem is so shot that they can barely stand the sight of themselves in the mirror. There is no way to make a social media post accurately describing such a state that does not amount to the emotional equivalent of rolling over and exposing your belly to the world. So it is rarely done.
A platform for playing status games does not incentivize genuine expression, especially at the darker end of the human emotional spectrum.
"A game is a structured form of play, usually undertaken for entertainment or fun". -Wikipedia
And remember - games are voluntary.