Both high and low percentages of carbohydrate diets were associated with increased mortality, with minimal risk observed at 50–55% carbohydrate intake. www.thelancet.com/article/…/fulltext
However like all dietary science: there is little that is settled. Processed sugars (low quality carbs) strongly correlate with being worse for you. The same cannot be said for whole grain sourdough or fresh fruit (high quality carbs).
Eating a fat and protein heavy diet based on animals has a 38% increase in mortality rate per year of being on the diet, but the same low carb diet using plant proteins seems to have a decrease in mortality.
It’s not settled but the studies mostly show that the best thing for you is to eat high quality foods and stop caring so much about macronutrients.