The fact is, the spoiled generation has really lower criminality rates, violence rates, takes less drugs then supposedly better behaved predecessors. People love to compare worst students now with best students of their generation or with their idealized idea of how great they themselves were - ignoring huge amount of people who dropped out of the school knowing pretty much nothing and that was it. Meanwhile, current best students are actually pretty good.
It is not all down to parenting changes only, but given better objective results the nostalgia for good old times is not really fact based.