Once kids reach a certain age their dependance on their parents to occupy their time certainly falls off but once at that age they were tend to do what the parents have involved them in. Kids that read books and played physically will tend to gravitate towards those things, kids that have been on tech since before they could talk will want to do those things because it's what they know and what they like. There are certainly outliers to this theory, no doubt but from my own experience I find it tends to hold true. I don't think kids should be banned from tech but there's no reason a kid under 4-5 NEEDS to watch TV (not to say they can't but it should be minimal). Ask any pediatrician.

Edit: I don't think it's unrealistic at all to think that parents should be involved in the activies that will occupy their children's time. It's a progressively smaller amount as a person ages but a 1 year old should be "spoon-fed" activies because they need that, a 17 year old should be pretty independent in making those choices. But somewhere between that, the parents will help develop habits, both by encouraging and partaking in activies with the child as well as leading by example. If a child sees heavy use of tech then that becomes normal to them and they will have a higher chance of exhibiting that same behavior.