I'm not an expert on this at all HF, but my understanding is that the healthiest populations throughout earths history have been those who primarily ate grains, basically 'higher carb' populations, and that populations that had higher fat had a higher propensity towards health problems / early death.
A lot of people make it seem like carbs are the issue in long term health but anthropologically it seems that the populations that ate primarily grains, legumes, etc had the least health problems and this is a trend that continues to this day.
I could be way off base here but that has always been my understanding. That being said I like having a reasonable amount of fat in my diet, I definitely notice an observable improvement in performance when they are kept at a reasonable/moderate place, but majority of my calories do come from carbs.