You know open-source doesn’t mean publicly available. It means the person, or in this case the US government, that brought the software should have free access to the source code to edit and distribute it as they like.

So yes, the military should use something functional equivalent to open source to prevent vender lock in and to allow for external audits. They probably shouldn’t give it to Russia or make it freely available online though.

If LLMs just copied stack overflow they’d respond to every question with “Closed as duplicate. Question already answered.”