[daxfohl]

I also wonder about whether there is a quality criterion there or is quantity all that's needed. For example if most dinners consist primarily of yelling at kids to sit down, eat vegetables, quit playing with food, just hurry up and swallow it, small bites, not that small, no poop talk at the table, inside voice, quit dropping your spoon, feet off the table, no kicking, don't annoy your sister, STOP SHOUTING.... Does that count?

[Enginerrrd]

Actually, almost definitely yes! Those things you mentioned, despite being friction areas, are actually loaded with all kinds of cultural and class norms, and the fact that you have parents who care enough and are around enough to be able to set those boundaries is a major selection criterion for success in other areas.

That's not to say you can't screw it up. If family dinners are spent in silence with the kids praying they get through the dinner without setting dad off again and watching him beat their mom to a pulp, or hoping that they don't get sexually abused later that night by one of their family members, etc. Then yes, maybe there are some quality issues, but I'd argue even in that extreme case, it might still be a positive indicator against the base cases of abuse without that element.

I was a paramedic. There is a massive fraction of society with upbringings like you wouldn't imagine. That's what you're up against. When people say they have a dysfunctional family, it's often pretty mundane. Especially compared to people in that class that didn't realize until they were an adult that things like getting raped by all of their mom's boyfriend's isn't a normal thing everyone deals with as soon as they start puberty.

[balfirevic]

That sounds outright terrible. Yes, it's not as bad as being beaten or raped (as mentioned by Enginerrrd in a sibling comment), but that's a really low bar.