Because of social media. Sports teams and after school clubs didn't go anywhere. Parks didn't go anywhere. Malls are in decline but the period of time they were an active social location was the 80s and 90s, which is a blip in the grand scheme of things. Community centers still exist, churches still exist, libraries still exist, basements and backyards and living rooms still exist. My neighborhood is full of young children who are always playing at the park, at each other's homes, at the pool. Yes, if you hand your kid a phone and a social media account to occupy their time, they will struggle to identify non-social media ways to interact with their peers. That doesn't mean those avenues no longer exist.
I agree with you that parents shouldn't be required to watch their child's every move, and I would go further and say that our modern society in general is actively working against parents ability to parent their children properly. But when it comes to social media, the facts remain: social media isn't remotely crucial for a child's growth or ability to socialize with their peers, they may in fact socialize better without it, and regardless, its extremely damaging and risky to their mental and emotional health.
The ancient Greeks went to the marketplace (το αγορά) as a social location. That’s where agoraphobia, the fear of public spaces, stems from.
Sports teams and school clubs haven't changed, and good parents take substantial advantage of them, sure. Community centers are all but dead in my town. The local youth centers I attended as a child have shut down. Churches exist; in my town, everyone who attends them is 60 and over. Libraries exist; they are near empty, or full of people quietly studying. Not a place for a kid to socialize. The local spaces that children used to hang out after school are empty, because everyone is at home playing games and using social media, and kids don't want to stop using them because the local spaces are empty. There's no winning.
These places are different than they used to be. The avenues exist, but there's no-one on them. If I told my kids to go play outside with their friends like people did in the 90s and prior, they'd be on their own. I'd need to start a societal revolution in my town with at least 50% of the other parents to get them to coordinate in sending their kids out as well. It seems like if it's not a validated group activity like sports or clubs, then people just keep their children at home.
I basically learned how to lie, sneak around, and keep two separate worlds going, as long as I needed my parents’ financial support.
I would argue that almost all of Gen-Z culture today is driven by internet communities and social media, and raising a child without access to online media will make it difficult for them to relate to many (not necessarily all) of their peers.
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