Is this a case of "here, LLM trained on millions of lines of text from cold war novels, fictional alien invasions, nuclear apocalypses and the like, please assume there is a tense diplomatic situation and write the next actions taken by either party" ?
But it's good that the researchers made explicit what should be clear: these LLMs aren't thinking/reasoning "AI" that is being consulted, they just serve up a remix of likely sentences that might reasonably follow the gist of the provided prior text ("context"). A corrupted hive mind of fiction authors and actions that served their ends of telling a story.
That being said, I could imagine /some/ use if an LLM was trained/retrained on exclusively verified information describing real actions and outcomes in 20th century military history. It could serve as brainstorming aid, to point out possible actions or possible responses of the opponent which decision makers might not have thought of.