I love how a lot of commenters are redefining “screen time” to suit their opinions or otherwise rationalise their screen time, rather than taking the study as is. I mean, sure, perhaps different types of screen time have different impact and this requires further study, but using anecdotes and opinions isn’t that.
The same thing happens with social media. It's fascinating to watch people bash social media on their chosen social media platform, under the assumption that social media is some other website that they don't use. That's why Reddit and Twitter full of people bragging they've deleted Facebook, for example. It's also interesting to watch the mental gymnastics people use to claim that the Hacker News comment section is somehow not social media for vague reasons (pseudonymous, moderated, technical niche, not mainstream enough) while ignoring the fact that we're all here posting content and up/downvoting it like the other social media platforms.