I don’t get you intro argument. An estate tax is like the poster child of value moved: from the parents to the children. In contrast to a wealth tax.
Seems like splitting hairs to me. If the estate is put into an LLC or similar then the death of a member doesn't involve movement of money. If the estate is owned by an individual and then inherited by their beneficiary then money moved from the deceased to the living. The Family is not a legal unit; the beneficiary doesn't have direct benefit of ownership while the owner of the estate lives.
By this logic, if I sell you a car, no money moved, because both the car and the money are still owned by the both of us. Or at least, if you're brother takes your car, you can't ask the state to give it back to you, as the car didn't really move, it's still in the family.
A family is not a single entity under any law in any country I know of. Certainly not in the USA or anywhere in Europe.
Are you going to drive me to work everyday after the transaction?
The difference is the kids have been spending estate money and have access to all the assets the estate controls. It make no sense that would change because a member of the family died.