Earlier quoted context omitted.
Because civilian made is not invented here?
I don't understand how you can even imply that it's because of a stupid reason like that. No the reason is that there are fundamental differences in the risk profile of the civilian and military sector. Adversaries will insert spies in mission critical projects if they are publicly accessible. Once the main contributors stop maintaining the project the military will have to hire people and train them for maintenance…
Have you heard of the cloud native computing foundation where members have committed to longterm investment in kubernetes development?
Kubernetes is the commoditization of infrastructure layers and serious forward looking companies are member of CNFC.
I assume you are aware of the history of Silicon Valley with defense contractors. And you probably also heard that the FBI approached Paypall for fraud detection capabilities. Hence Peter Thiel's venture Palantir.