Hey Krista, good writeup. I also think it's easy to "misjudge" keto as a fad diet you are correct, it's being investigated for a lot of therapeutic purposes right now.
In fact, until the last 100-200 years humans likely spent a lot more time in ketosis than we do today. Keto is probably a lot closer to a normal human diet than our current "Westernized diet".
What I would really love to see is more research on whether the benefits of being in ketosis are coming from the ketones themselves vs simply not eating carbohydrates or having low insulin.