Demand driven MRP doesn't square up with Amazon making a profit on $7 item sold once per year from 90 million SKUs. Likely the problem solution lies in follower and leader forecasting via graph database analysis.
Decoupling deep level ROP parts, putting them on color coded buffer watch makes sense for planner action analytics. What doesn't make sense is not using color coded analytics on sparsely sold end items. Amazon has mastery in this supply demand domain.
Actually MAX and other MRP systems added sales order driven MRP years ago. MAX even had a color coded planner action analytics designed by Rodenrys / Juhnke. Case in point, I only saw a very few of the most savvy customers tweaking ROP in Excel, those with $50m+ revenues.
Thus the DDMRP while terrific for complex assembled items by concentrating on operational demand misses on certainty of demand by not applying data science techniques Amazon uses to peel profits away from competitors. Why is this so hard for the ERP industry to grasp...