"And, who can doubt that his fears that the neo-Malthusian agenda of the population control experts was a grave threat to human dignity? "

Well, myself, for one. The planet already has more inhabitants than it can comfortably support by a couple of billion people, and the population is exploding out of control exponentially. For Catholic hierarchs to bury their collective heads in the sand like an ostrich and pretend that we are not headed for a human and ecological disaster simply in order to prop up an ancient ban on artificial birth control that should have been tossed out eons ago is just plain ludicrous. 

Despite the other aspects of his greatness, the left was right to give up on Paul VI after "Humanae vitae." He ignored his own advisory council's recommendations and made the wrong decision, the cost of which was the loss of moral authority for generations lasting all the way to the present day. That was a pretty stiff price to pay. Was it worth it? I would say no, it was not.