I mean, your second and third paragraph could be the introduction to an internal presentation about "why we at Amazon should embrace, extend, and extinguish OSS". The things you listed are precisely why Amazon would want to destroy OSS, Because OSS is a threat to anyone offering proprietary software, and anyone who has built their empire on OSS will inevitably need to shift to proprietary software to retain relevance in a world where OSS software "eats the world" by, for instance, commoditizing the infrastructure layer...
In other words, just in time for AWS to become less relevant due to the enormous gains in open source infrastructure as a service tools, Amazon will swoop in and help to destroy the most useful parts of the open source economy.
It's easy to look at this with a naïve optimism and think "but these are the exact kinds of things that helped AWS grow to begin with", To which the obvious reply is "yes, at the bottom end, but Amazon has been focused on enterprise more and more over the past five years, and licensing agreements with other big tech companies have changed the offering and the prospects of future offerings". All you have to do is look at YouTube to see another example of this. YouTube built its user base on small contributors, but as soon as it reached a plateau it began to focus on the old guard, main stream media, Hollywood, etc., unfortunately for the little guys. This is the same pattern every company takes once they get big enough to play competitively with the big boys.
This is all, of course, only my opinion.