Not Black and White
Thinking back to my own childhood, I can say that in fact technology and computer games had the exact effect that Ellison describes - and it was the best thing that could have happened for me.
I grew up in a relatively poor area. Thankfully not the hell that inner city kids have to deal with but the kind of place where 8 out of 10 families (mine included) were dependent on benefits of one form or another.
As a young child I'd go outside a lot and do all the usual stuff such as making tarzan swings, camps in bushes and things like that (didn't have a bike until I was 12 as we couldn't afford one). The people I'd do these things with were not nice (I knew right from wrong) and along with the good, wholesome activities there were the games which involved setting stuff on fire and other antisocial stuff.
That all changed when I got my Sega Master System (saved up all year). Now I finally had something to do, which didn't involve hanging around with mini-chavs. Then when we could afford the Internet, that really allowed me to become the person I am today. I could talk with those with views like my own and it allowed me to see that there was a whole world out there to experience.
Fast forward a few years and now I'm doing well. I'm a software developer with a good degree from a decent uni, a good few years of experience and will soon be buying my own house. The majority of the kids I hung around with are either dead, in prison or on benefits with a horde of little bastards of their own.
It's true, computer games and other tech can prevent kids from going outside and in my opinion, that's a good thing.