Alot of pseudo science. The biggest factor other than just getting fat and maybe getting diabetic from abundance of sugar is still in fact saturated fats.
The "carnivore" or keto fanatics are often(always pretty much) not based in proven science. If you ignore proven science sorry you are pseudo pusher and I can't take you seriously.
Also, a well balanced in macros diet is still the best and always will be the healthiest. Carbs are also needed especially in sports/physical demanding activities for optimal performance, we are made to run on this most efficient fuel for our bodies when placed under high anaerobic stress.
Kevin Mann brought up great points re saturated fats. He is Vegetarian but for ethical reasons. His points are still valid.