That is an awfully strong statement. Do you have qualifications to dismissed the entire field, or is more of an opinion? And even though it's not up to your (admittedly best case) standard, don't population studies, twin studies, et al have some value. It seems it would be effectively impossible to research anything at all about nutrition otherwise.
Overall a good write up, but that they end with a consensus statement by nutrition researchers after explaining why no nutrition research is really capable of telling us anything is just about the perfect encapsulation of what is wrong with nutrition research and reporting on the subject.
Show me your favorite nutritional study and I’ll be happy to explain why it can’t actually tell us anything about the long term effects of diet on health.