I see your point, but I take issue with a few things.

The first problem I have is calling sitting for 20 hours at a computer an "ability". I think that would be more of a "susceptibility". It's not like it's a skill.

The second is the idea that the biggest problem is a loss of productivity. That's true, and some of them would best be put to use doing tech support...if that was the kind of thing that makes someone hooked on the internet. It isn't all content that is addictive. Most people's jobs deal with the web, but not on the sites that they want to spend hours and hours. It's like trying to get someone who eats junk food constantly to switch up and eat broccoli constantly. It might be healthier, but it won't erase the craving. They have to get their schedule regulated and their exercise going, etc. The biggest problem for the internet addict isn't a lack of productive options, its a strong affinity for unproductive options in spite of knowing better.