Even if so, in my experience most folks seek to maximize the yumminess of whatever diet they try. So if they like stir-fried rice, they will eat that unless the diet expressly forbids it. Granted, I'll bet buckwheat groats aren't particularly yummy, so there probably won't be many folks eating that.
1) I do what works best for me, informed by science, the experience of myself & others, traditional knowledge, etc., not blind re-enactment or "noble savage" notions.
2) YMMV. Don't imitate me--find what works for you. The only fact I know for certain is that of my ignorance.
3) When I report health results, it doesn't mean I think they apply to anyone else. Iím not prescribing.
4) It may help discussion if neither of us tries to speak for the other.