Here's a different take on this perspective. It seems to be demonstrably fine that most people occasionally drink some alcohol. But obviously, if everyone was drunk all the time, society would collapse.

Similarly, we could instead say that yeah, maybe TV had some negative effects, but there's no TV outside, at work, at school, at least not usually. And at least for TV, you turn on a channel and watch it. Also there's some pretty good stuff on TV. How many scientists were inspired watching Star Trek as a kid? But I'm sure there were kids who did watch too much TV, and it really did have a negative impact on them. It's just that eventually norms were established yadda yadda that mitigated the severity of it on a societal scale.

With smart phones and social media, maybe we're scaling up the sorts of negative effects that people were worried about with TV, to where it really can have some disturbing effects even on a societal scale. And maybe we really should be worried that we're effectively conditioning children to have shorter attention spans due to the emergent properties of a smartphone with multiple different social media apps firing off notifications with very short form content. And the rate of adoption has been so huge, that if it is the case, we might already be fucked pretty soon.