you should probably give the article a read, my main takeaway from your post is that people love to talk about what they eat. I will remember it next time I have an awkward pause when conversing with a stranger.
I read what he wrote, I just disagree with it. Nutrition is not really so simple and this information is both useful and objectively true. It is also relevant to the subject being discussed. I think the author has an overly simplistic and misinformed view of nutrition, so I am providing useful and relevant information.