Actually, this is a matter of Buddhist sects. It's not that you're wrong—the etymology is correct—but I think you're taking the historical changes too lightly. Because generally speaking, there is Mahayana Buddhism and Theravada Buddhism, and they usually follow the Pali tradition. In fact, the concept of 'emptiness' (Sunyata) in Mahayana Buddhism is itself based on non-duality. So what you're asserting is not wrong as a source or an original form of Buddhism, but regarding the description of Zen in the article, the actual Seon tradition is generally closer to what I'm claiming. In fact, you can't really talk about Seon Buddhism without bringing up Taoism, because during the process of its transmission through China, it merged with Chinese folk beliefs and then spread throughout East Asia. (For reference, I'm Korean, and the Buddhist traditions in Korea were also heavily influenced by China.)