I was an undergraduate at Cambridge in the 1960s and saw at first hand the effects exclusive schooling has on human beings. All were marked by it. Some were ill. None had much idea how most people in our country lived.
What excellence can we expect of a 12-year-old who is responsible for where his or her parents live? It just inflates the self-importance of children if they are treated like hothouse flowers.
The men and women of this country would do better with a common purpose. But while the leader of the Labour Party ditches his education policy just to keep his son away from ordinary people, there's precious little chance of it. What on earth are you excusing him for?