Then you wasted an opportunity to learn something from a very insightful article because of a superficial detail. I'm not entirely sure why that's something you're proud enough of to post a comment about it. Seems like a flawed outlook on life to discard a message because of a single superficial detail in its delivery.
If everyone had infinite time to read articles on the internet, it would be best to keep reading and possibly learn something useful from the article despite its error. Since we don’t have that much time, we have to decide which articles are worth reading – there is a lot of nonsense on the internet that is a waste of time to read (Sturgeon's law). Errors of sufficient number and magnitude at the beginning of the article indicate a higher likelihood that the rest of the article is too nonsensical to bother reading, i.e. that the ratio of usefulness to time spent is too low.
Now, maybe you disagree that a graph with loops is that big of an error. But then you should write about the graph specifically. I don’t think you have grounds for disagreement with the basic principle of generalizing the quality of an article from part of it and using that estimate to decide whether to continue spending your time on reading that article.
