Unaffiliated being a critical part there, because of course Microsoft, AWS, etc contribute back to these projects. But, many, many of the developers on these projects are unaffiliated, often working at smaller companies/consultancies with no affiliation to the megacorps that make billions on the software.
Yet, I've not once noticed a single instance of aforementioned drama. What makes Docker, MongoDB, etc different? They're open source products developed and monetized by singular corporations, not communities or non-profit cross-functional organizations like The Linux Foundation. Its a big corporation slighting a smaller corporation.
This may reveal a bias in online discourse, especially on HN; we revere corporations, not people. We want to protect venture-backed Docker, but the individual developers working on, say, Postgres? Less deserving. Peter Eisentraut, Bruce Momjian, and Dave Page are core maintainers of Postgres, all working at a company named EnterpriseDB, who sell managed Postgres offerings. Why doesn't anyone complain about AWS screwing over Postgres?
Well, there's something bigger at play: Its actually, totally alright if megacorps use Linux, Postgres, whatever in this way. Developers enter these projects knowing it'll happen, and these projects are healthier than ever. That's a beautiful relationship right there! No drama. No one slighted. If these companies give open source back, that's great, but I don't expect them to (exempting GPL requirements of course), just like no one expects me to contribute every bit of code I write just because I coded it on Ubuntu using vim and linux and gnome and docker and such.
With Docker (and similar corporations), someone is slighted; its the company that was also trying to make money on it. And I think that's just mismanaged expectations at every level; the company believing they could build an OSS community of users and builders while still extracting profit, the leaders for accepting venture capital, and the users believing a company could solely develop and distribute something as complex as core application containerization or a database.
To be clear: I have a lot of respect for Docker continuing to run Hub for free as long as they did. They're an awesome company. No qualifications around that; I hope they find success in the market. I just don't believe that success will come at the scale and valuation they expect, because they aren't selling what customers want to pay for. AWS is.