A little bit more specifically, the exact failure mode is in properly identifying that mammals that are prevented from playing in multiple animal studies pretty much turn into complete F-ups when they become adults, and properly scientifically documents that human kids are prevented from playing more over the years while perhaps coincidentally mental illness levels have exploded in children.
So the specific failure mode is proving that totally F-ed up lower mammals equates to suicide in human teens. Probably the only really scientific conclusion you can gather is that forcing human kids (aka mammals) not to play screws them up horribly.
Well, I'd love to sit here and debate with my HN buddies but as you know the only hope for a middle class lifestyle is being in the top 5% so I gotta take off and helicopter my 2nd grade daughter from Violin lessons to Chinese lessons to Lacrosse League practice otherwise she'll never make it into Stanford.
Note I'm kidding, I don't even let my kids join organized sports, although we participate in totally dis-organized sports (aka, actually fun) at the park a couple times per week. My son's actually getting good at hitting a baseball, although no one keeps score.