Honestly I think there's a lot of sense this, maybe even it being a no-brainer. How could anyone not think there'd be a change and a child being left alone to watch TV and parents sittong down to watch it with them.
Whether with learning or simply keeping a child entertained, a parent there should make a difference. More it should be considered that using a TV as a babysitter or otherwise having technology be the one to keep a child busy only make it so that a parent has less ability to structure what is seen by their child.
Finally, when parents are willing to sit down with a crowd to watch what they want they wouldn't be more likely to care about is watched by their child.
I think that TV is too rapid-fire. It overstimulates children to the point that they struggle to 'slow down' to regular life. If parents just leave children in front of the TV for hours, they are getting a lot of over-stimulation and their brains get used to that level as a base line, then later when parents want to do something with their kid, the kid gets bored or loses interest quickly, and the parent feels like they can't connect. Then it become easier and easier to just leave the kid to watch TV, until they go to school. Then in school, nothing happens as quickly as on TV and the kids can't pay attention and get diagnosed with ADD or ADHD and have to be given drugs to help slow down their mind enough so they can focus.
I think TV can be a great educational tool, but nothing can replace having personal interactions and taking time with your kids to teach them how the real world functions, even if that is just playing with them in person at a 'regular speed', so they don't get over-stimulated.
Moderation, that I feel is key. Allowing children to watch tv, especially if you are able to sit down and watch it with them, is fine. Allowing them to watch tv or the computer for hours on end and unsupervised not so much.
Parents need to be aware of what their children watch, be active in keeping them from that which may not be so good for them and to make sure their children do other things.
Parental responsibility, which is why I find it frustrating when other blame entertainment such as video games or movies on what is causing a child or one even going into their teens to do what they should or misbehave.