The current discourse seems to be based mainly on insinuations that FB/IG actually harms people on the basis of a small fraction of struggling kids reporting that they feel worse when they look at Instagram. But, would anyone have predicted otherwise? That literally no teen who reports suicidal ideation would attribute their issues in part to what they see on social media?

Or perhaps that's a strawman -- would we not have bothered with this discourse if the reported fraction of teens reporting suicidal ideation who cited Instagram were 2% instead of 6%? 1%?

Given how many and how much young people use Instagram, what fraction there would represent "no effect size", where you can't get away with insinuating that Instagram has any causal impact on mood compared to any other activity that kids could be doing? It's probably not 0, right?