From my POV the most productive growth amazon can make as a company would be engaging in better ESG practices There are forms of capital outside of material assets and intellectual property.
Amazon is losing human capital (tbray as a high profile example, but I am sure he's the tip of an invisible and silent iceberg)
Amazon is losing brand capital which will hit the bottom line (ethical consumption is an ever increasing trend)
Amazon will continue to irk Governments with its lack of respect for sovereignty laws (tax in particular, but also labour and monopoly).
Invest less in growth and more in the human capital that is essential to running the business.
Playing by a different set of rules guided by Jeff's meglomania has driven them to the top and that is laudable.
Once you've conquered the world do you still need to keep squashing the people you lead? What is it serving at that point other than pure egotism ?