At face value, I'd agree - however, looking into it just then, it may actually be a myth. That may be something Brian has also determined.
I'm sure I want Brian to make sure that his child isn't destroying his lower back at the age of 7
I saw an SF guy talking about how he raised his kids. He said he saw his kid hanging off a tree branch on his property, thinking he will sure break something if he falls. Thinking it over he thought it's better he falls off here than if he climbs something higher and dies; he will learn a lesson so he didn't intervene.
I don't know exactly how this applies to Hankins, except that kids constantly jump off things, run and squat and put their skeletons through a lot. Kids are resilient and squatting isn't inherently dangerous. They twist their bodies in many "unnatural" non-ergonomic positions.
Though what I saw in his kid's squat video was that the kid didn't have his feet even. That might be something to adjust for Hankins before the kid descends into a squat.
This girl has excellent technique but the lift still puts stress on her joints. I have nothing against this, I don't think it's child abuse.
There is bend in the back and so on:
I'm trying to find a video series of a woman training her little girl in powerlifting since a few years old.