fairly true.
I've received horrible nutritional/supplementation advice from a general practitioner.
Unless someone specializes in nutrition or is a huge part of the studies, they're just regurgiating info much like we are.

Nutritionists don't even agree with each other. You'll have anti-meat, anti-dairy, anti-gluten, anti-carbs, pro-carbs, etc within the community. The bottom line is different things work for different people.
But when a cyclist asks if a glass of milk is "bad" in terms of health/performance the answer, in my opinion, would be no. Especially in terms of performance.