Depthless: The New Uncanny?

This amusing piece in the New Yorker by Brad Leithauser discusses that the word "depthless," like Freud's uncanny, means its own opposite. He calls such words "auto-antonyms." On the one hand, "depthless" is a synonym for "unfathomable"--i.e., so deep that you can't tell how deep it is. On the other hand, it means "having no depth,"--i.e., utterly superficial.