Almost got it.

Point is, it doesn’t have to be bad parenting, that’s just the narrative. But if not, what is it then? What’s the foothold? As far as I can tell, it’s to protect children since that’s the narrative. How was that foothold given to them? They don’t need much to work with. If it were evident there were no foothold, there wouldn’t be one.

And, you’re exactly right, they would look for another if we had this one defended well. It is evident what the end goal is, but a defence is by minimising chinks in armour. If there were strong contrasting evidence to the very few bad parents, it wouldn’t be a foothold—they couldn’t use that narrative. But they seem to think there’s just enough of a chink for pressing fallacious generalisation.

Everyone knows kids just get around it all anyway, so that’s not the point, but they’re in because there was enough to make use of secundum quid. That’s almost always how authoritarian shifts worked in social history if not outright oppression through violence. We know it’s bullshit, but it works like that, unfortunately.