> When you're on the internet, you're engaging in bite-size activities and constant task switching.

Sometimes. Sometimes I'm doing one thing and focusing on it.

> Quick, how many tabs do you have open right now?

Not the greatest metric. When I'm working, I often have like seven tabs open, all about what I'm focused on working on. So why would we assume that "number of tabs" is a better indicator of unfocus when discussing leisure time?