Social media and computer games in general.
Very different from today's pay-to-win manipulative Skinner Boxes, but probably not very healthy. Living someplace where I couldn't physically hang out with other kids easily after school (thanks, car culture) it probably helped me build better social skills. But at the cost of my attention span and physical social skills.
It certainly makes me wonder what skill tradeoffs today's video game kids are making.
Potency and availability matter. I've heard of multiple cases of kids soiling themselves rather than stop playing a game. I never heard of that growing up surrounded with video games.
https://www.news24.com/life/archive/how-a-9-year-old-became-...