Good points, I agree that it seems unlikely that Amazon has lost sight of the long term thinking that is largely responsible for making them Amazon. And it is

Good points, I agree that it seems unlikely that Amazon has lost sight of the long term thinking that is largely responsible for making them Amazon. And it is indeed an arms race, like everything that happens on the internet at scale where money is involved. But I disagree that the problem is prohibitively hard to solve. In my experience you can always stay just ahead of the black hat players. They're rarely smarter or more talented than competent software engineers and data scientists. Amazon's failure to stay ahead in this area is, to me, an indication that they're using the wrong strategies, probably because people with the wrong skillsets are being assigned the job of figuring out how to solve the problem.