Yes, most of these "nutritionists" were taught directly by a pet food manufacturer, and those who were not, were taught INdirectly by one. Remember that vet schools are all funded in part by the pet food industry--most vets are the last people to listen to re: nutrition as a result!
The best "nutritionist" is Mother Nature. She's been feeding carnivores a species-appropriate diet for MILLENIA now--a whole lot longer than the 60-70 years the pet food industry has been doing so. Get as close as you can to a whole prey raw diet and you'll be golden. Kibble is as FAR as you can get from that.