Why do we have to wait for anecdotal reports? There are numerous people who have followed this diet for decades in the US, but more importantly, there are entire tribes of humans who have eaten carnivorous diets for thousands of years. How much plant-based foods do you think the average Inuit consumes?
1. Bigger groups === more and better data. I didn't know anyone growing up who was interested in ketogenic or carnivorous diets, now it's much more common.
2. Huge difference between the diet of a westerner following carnivore and traditional tribal carnivorous diets
4. And most importantly, there's a lot of research showing that high levels of IGF-1 associated with diets high in red meat are not good for longevity: https://www.youtube.com/watch?v=AjSl4n_KdOY