Social media ≠ social connection, for the most part (i.e. the proportion of time spent messaging vs. passively viewing is skewed towards the latter).

That's why it's trash - it's a pseudo-relational avoidance of both the greatest rewards of connection but also - crucially I suspect - of its most painful liabilities (i.e. no one's heart is broken if a pseudo; relationship ends).

And since humans are naturally biased more towards avoiding loss than seeking gain, social media takes over the world and online becomes the default place to hang out.

A world which in aggregate no one wants becomes a reality because of narrow preferences repeated over and over again and at scale.