It varies a lot. My kids will run around and play given the opportunity, but when they arrive home at 6pm from after-school club, completely exhausted, I think it's fair that they get to collapse in front of a screen for a bit.
For my generation (just post-Boomer), it was the TV.
For my parents, it was the radio.
For their parents, reading out loud for everyone to enjoy ("Mr. Dickens has published another episode of The Pickwick Papers!"), or playing instruments.
Problem is for the first month of lessons it is not joy, it is hard frustrating work where you sound bad and know it. Even when you are good lessons often are pushing you to do hard things and so they are not pure joy.
My son has been taking violin for years, is really good, and loves it - but most of his practice time is still really hard pieces that need a lot of practice of the hard parts (stitching between 5th and 2nd position...) and he would prefer to sit down at the piano (he stopped lessons years ago) and play an easy piece.
Practicing is always hard and I struggle to find time or energy to push myself but my goal was to be able to play basic chords and make up silly songs around the campfire so everything else is just a bonus.
Individual screens can be isolating, they can also be somewhat social. I agree, not a complete replacement for other social activities for sure. But, as a kid with internet connected videogames growing up, those internet connected games kept me playing with friends from school and other groups even if we weren't able to physically get together that evening.
Meanwhile, my brother would often go dig in and read a fiction book in isolation. Which is fine and great and all. I'm definitely not taking a dig at reading a book in any way. But, its not like only screens lead to isolation. There's plenty of tasks one can do at home that then become isolating.
For a lot of young people the screen is social - the equivalent of the long after-school phonecalls from the before times. Be it games or just Discord, it's still comms.
The screen is also a continual, addictive flow of short video clips that are largely designed to sell product, stoke FOMO, make people feel inadequate about beauty, etc.
Observe young people using their phones, and you can see the social use is often just occasionally switching from TikTok to a chat app, dashing off a one-line message, and then going right back to TikTok. Big difference from having actual long phone conversations with friends after school.
Most of the social of screens is when you get to a place without them you have something common to talk about. "how about [local sports team]", "what did you think about [whatever happened on latest soap opera]", "lets pretend I'm [some character on cartoon]". It is all shorthand for we have something in common and can skip getting to know each other.
