I do follow something close to it, yes, because of Crohns disease and coeliac, I found it the best way to manage the condition. I’m not a slave to the dogma though – I did give up all grains for a while, but I eat white rice now sometimes and also use gluten free tamari soy sauce and miso in cooking, because I refuse to pay £7 for a bottle of coconut aminos, and I also figure the Asians do pretty well with rice and fermented soy – lowest incidence of crohns/colitis, heart disease, obesity etc in areas where they follow traditional diets.
I found the biggest benefit probably came from giving up processed stuff, cooking from scratch, and eliminating dairy, but an awful lot of people with coeliac disease have a lactose intolerance so no big surprise there.
Mol makes a good point that nutritionally, it’s a pretty sound diet, but that the “ancestral” claims are dubious. What your ancestors ate depends very much on your genetic makeup, and that’s down to the individual. It has also been hijacked by the “body beautiful” types somewhat, which can be offputting, but for people with certain health conditions I think it can make a lot of sense.