I‘d wager that the correlation is with how exhausting the parent‘s job is. Screens are excellent for keeping children occupied, keeping them happy in healthier ways requires a lot of energy. After working a hard job, running a household and worrying about whether you run out of money before the next paycheck I can imagine that many parents just don’t have the mental resources.
If that was true you would see unemployed parents being best at keeping their children from the screens. It is awareness, i am pretty sure about this.
> Screens are excellent for keeping children occupied, keeping them happy in healthier ways requires a lot of energy.
It could also be that the parent wants to be on their screen at the same time, or wants to be on Instagram later into the night. There will be some correlation with work, but I doubt that explains most of it.