Feel like you've massively glossed over Amazon's strategy. From working there, data-driven decision making and automation permeated throughout the whole company culture.
For me, this was evident from the fact that quite literally everything was automated:
Physical SKU distribution was allocated by an algorithm, optimizing for space density and picker path length. Pickers carried trackers to enable the data to constantly be gathered and algo performance reassessed.
Prices were automated in real-time
Inventory management and purchasing was automated and humans were there to override when necessary.
Kiva was purchased and applied to implement an inventory store that can self-reorganize in real-time
At least in my mind, this goes far beyond the token "we do A/B testing on UX" that other webshops do.
Worth also mentioning that Amazon did collaborative filtering on book recommendation way before it was trendy to do...
When I squint, it feels like Bezos had some image of some giant razor thin machine (quite literally) selling commodity goods, constantly capitalizing on competitors' inefficiencies. I can't help but feel this was inspired by his time spent at DE Shaw...