Read other letters about this article
Plagiarism is citing someone else's written word, or as close to as makes no difference, without giving credit. There are millions of ideas out there at any one time and lots of people rework and update them. This may suggest a lack of creativity but it is not plagiarism. Plagiarism (like traitor) is not a word that should be used lightly.
I think the article is crap for other reasons but, technically, it is not plagiarized.