I wouldn't call it disingenuous at all, it just helps to make one particular point without also complicating the picture with various other factors.

Many who argue against low carb on the grounds of "keto flu" style symptoms will often cite those shorter studies as the basis for their arguments. What this study demonstrates is that yes, there can often be side effects when first getting underway with low carb, but also that those symptoms are temporary. Past the first 2-3 weeks, things tend to work out much better in terms of TEE in the long run. That's the real point behind this study as I see it.

Yes, this may well have incorporated some studies where the definition of low carb might not quite agree with ours. But think about this: if a study like this had been done by assessing only those studies where carbs made up a maximum of say 20% of energy intake for example, the results may very well have turned out even better from our point of view, but at the same time, would also have given detractors an opportunity to argue the point, that not all "low carb" studies were considered, that the data was "cherry-picked" or whatever. And by their definition, they would be right. By including more liberal low carb studies in the mix, to actually meet their definition anyway and still demonstrate successful outcomes, that really leaves opponents with no room whatsoever to argue that particular point.

Could the results have turned out even better if eligible studies were limited to only those with even greater carb restriction? Probably, but that's not the purpose of this study as I understand it. That would be the subject of another study for another day.