debatable, in my opinion. The diets were "keto like", not confirmed keto, and depended on personal reporting rather than actual monitoring. IMO, the results would be more useful if individuals were actually tested through the entire study to confirm that they were in nutritional ketosis. Not only was that not done, the diets included were often, if not mostly, just higher fat diets but not sufficiently low carb to put and keep individuals in nutritional ketosis.
Another issue re. applicability to me personally is that I am not on keto to lose weight, I am on it to control type 2 diabetes. Unless a test properly compared diabetics on keto vs. diabetics not on keto (and therefore likely on other diabetes meds like Metformin or Insulin), the results would mean little to me. Also, I am only ~145lbs and very fit, so the test would have to include other diabetics like me, stratified by weight and condition. I will not be holding my breath for that study to be done soon, but you never know. Academic papers on control of diabetes with keto diet have started to be published, but there is a lot of work yet to be done to clarify all this stuff.
Bottom line for me is that keto achieves normal blood sugar for me (A1C of ~5.7) without medication. With medication, the normal sequence is gradual increase in meds to try to deal with the body accomodating to them, and most peeps end up on insulin eventually in spite of best efforts, and many end up with organ failure and/or amputations later as well. Not my cuppa, I will accept higher cardivascular risk (if indeed it would actually be higher than risks of diabetes, which I still seriously doubt). We are all going to die, and a quick heart attack would actually be one of my preferred options. But not yet...