"Screens bad! Go outside and play!"
The child might be doing something mindless, or might be involved in something fascinating - creating or participating in elaborate and vibrant virtual worlds.
I think parents should seek a healthy balance for their children. But that means understanding what's happening and what it means and not trying to promote activities because of how they look on the outside. A child riding his bike around the neighborhood probably looks better to modern sensibilities than one staring at a screen, but I don't know why bike riding should be considered superior to building a world in Minecraft as an example.
Nothing against fortnite, but we are animals with bodies, not brains in a jar.
This is why I'd say that riding a bike around¹ is more valuable than playing fortnite.
1: And bike riding can be a group thing as well. When I was a kid,we dirt jumped and mountain biked on the local trails a lot, which was immensely fun.
Speak (emphasize?) for yourself; I'm software that happens to be installed on a meat-puppet.
If you truly believe that, then quit your office job and take a more physical, human occupation.
I used to work farm labour when I was younger, never slept so well in my life.
The key seems to be catching a view of someone at a computer or in front of a TV or whatever but not also being able to see what's on the screen. It's chilling and creepy for reasons I can't quite put my finger on. Maybe it is just the "zombie" factor, I dunno.
Staring at someone staring at a screen? Yelling at someone staring at a screen?
Neither of those are technically alone, but that's the point: Bothering someone else is infinitely worse than... you know... not.
[EDIT] I think "using a computer" posture especially is the worst. Something about sitting upright at a desk or table using a computer is really weird. Like the person's body's subservient to the activity, while also being kind of absent from the whole thing. It's much worse than bending-neck-to-use-a-cellphone or slouching-on-couch-playing-console-games look.
There is not much positive to say about sitting in front of a screen all day as a person, less so as a child.