The authors do consider these issues (though perhaps not to your satisfaction). They say that the longbow was only really effective en masse, requiring the participation of the yeomanry, and that the duration of the period of English longbow dominance, and the number of against-the-odds English victories in that time, provided both the motivation and opportunity for its opponents to develop the same capability. They argue that the French were well aware of the threat that English archers presented, and frequently avoided battle on that account, preferring to recapture territory after the main English army had moved on. In the quote on page 703, they offer a contemporary account of the French beginning to adopt the longbow, but reversing the policy precisely out of a fear that it would enable insurrection.<p>From my limited knowledge of medieval society, I think the nobility would have considered archery to be completely beneath their dignity, and an affront to chivalry. Their proper place was on a horse, in armor and wielding a broadsword or lance.