I always found the idea of limiting "screen time" quite odd. Because this can mean so many different things, from playing games, writing messages to friends, using social media, reading books. Which can end up in some odd contradictions, because e.g. "reading books" is often considered as a positive thing while "screen time" is considered negative. So does "kindle / ereader time" count? Is cooking also considered screen time if you look up a recipe on the Internet with a phone or tablet?
I think the idea of "screen time" limiting is rooted in an odd suspicion around technology and an unwillingness to consider the impact of the individual activities.