While shoving a mouse around and typing does not seem like significant exercise, I think there's a bigger energy expenditure in interactive thought. Zoning out at the television does not engage many areas of the brain, but chatting with friends or deciding where to browse next takes a bit more power. Brain activity burns calories. I've personally noticed that my head warms up more when I'm thinking, especially if the work or play is cerebral or there's a time pressure involved. It would be very cool to see a study on just how different these tasks are, with brain activity monitored objectively.
Agreed, but the life and death wasn't the point. Regulation was the point. Over-regulation sucks. The question is whether the fact of regulation is reasonable.
You've indicated that life and death obviously merit regulation. And you've said that distraction might be just cause.
Banning screens is regulation. Maybe it is over-regulation. So what would be reasonable?
Only through hard work and perseverance can one truly suffer.