Dubious at best. If one has children they notice quite visibly that screen time makes their children more agitated during the days they have screen time. And screen time is as addictive to children as it is to adults, and we should consider the effects they have on their developing brains.
My personal observation is that "screen time" is not the problem, but lack of interaction _is_ - letting the kids be in front of a screen for two hours doesn't cause a problem, but letting that be an excuse not to spend time with them or interact with them (which is when it usually ends up happening in large quantities) does. Essentially - you need to control the other variables to understand what's really going on; excessive screen time is generally a symptom and not a cause.