I think there can be a balance but people underestimate how bad seed oils are. It takes like 7 years to detox from it. I do think carnivores are extreme. Your brain uses sugar for energy and muscles store sugar for power. Converting fat to glucose is inefficient for athletes.
Discussion
Oh yeah I'm not a seed oil proponent. I stick to animal fats, plus olive and avocado oil for cooking. Both of which have been used by humans for hundreds of years.
The modern seed oils require huge amounts of processing, which is where the danger lies. In whole foods the amount you actually get is negligible, plus they haven't been through the chemical/heat/mechanical processes that make them dangerous.
I used this way of looking at food to drop about 40% of my bodyweight, after a life of eating primarily processed food, and I've kept it off for over 12 years now. I just try to eat primarily whole foods, cooked by me.