I'll answer your question and why I agree by using a couple personal academic experience relating to the MI.
Reading about the short theological introductions is really frustrating for me. The line up of authors seemed pretty impressive, and I was excited to see what they could say about the rich theological material in the war chapters. (If you don't think so then you were the perfect audience for a brief theological introduction.) Instead, the author did a podcast and happily said right way that he ignored it. It was very disappointing.
When I asked them about why they ignored such a large chunk of valuable material they accused me of being uncharitable, which, ironically enough, I found very uncharitable. Then they said they just didn't have room, and couldn't dictate what the author wrote. I found both answers very unsatisfying.
On not having space they sounded a bit like the Game of Thrones creators in the last season. Inexplicably, they shortened the last two seasons of the most popular show in the history of tv. When faced with criticism about the lighting pace, they said they didn't have room to cover everything. Yet they were the ones that chose the length! Simply adding another book to cover the war chapters didn't seem that tough. One of their earlier authors devoted a whole chapter to the 700 words in Jarom so maybe they could have spared a bit more for 20 chapters.
The author choosing what to write was an even worse answer. The editors didn't say, "maybe we should find a good military historian or ethicist to cover the dense war chapters," they invited a Heidegger scholar and then pawned off the ignored material as the writer's choice. As if they didn't know what he was likely to write about and what he was likely to ignore. The cherry on top was when they got defensive and accusatory when someone noticed their significant lacuna. So they missed out on what could have been the most useful and interesting book in the series, so a Heidegger specialist could Heideg.
My reaction to the series is pretty emblematic of other MI publications and the larger point introduced in this thread. Their books seem scholarly. But they also seem invisible because they spend most of their time on theological and philosophical musings that aren't interesting or useful for my life or a broader audience. They don't offer books about history beyond the 19th century, responses to criticisms, or many other things that average saints want to read. Being academically rigorous is important, but so is accessibility for the audience and they love the former to the detriment of the latter.
I have a review copy sitting on my desk of a Latter Day Saint/ Shinto memoir interspersed with haiku. It's nice and I appreciate that person sharing his journey, (I also appreciate someone at the MI looking for LDS scholars with a background in Eastern thought- keep an eye out for my book on classical Chinese military theory beyond Sun-Tzu). At the same time the book doesn't do anything for me so it's probably going to gather dust on my book shelve until my next run to DI.
You speak about relevance and I agree. They seem kind of invisible or irrelevant because their research priorities often make them so. Some of that is simply based on academic background and taste, and maybe some ignorance, but I think you bring up a good point.