Meh. If I understand you correctly, you're saying that a humanities PhD might not have practical value, but it has value to some people because they like it and come out of it more worldly. I mean, sure, okay, but there is a qualitatively different type of advantage that comes with a technical PhD.
I don't disagree with you on any particular point. I was only stating that to dismiss a PhD in the humanities "as a waste" says a lot more about the position from which one makes that dismissal than about the humanities PhD itself.