Are Elvish, Klingon, Dothraki and Na'vi real languages?

Fantasy constructed languages (or conlangs) have the complexities of real languages e.g. a large vocabulary, grammatical rules etc. Linguist, John McWhorter (Columbia University) explains why these invented languages continue to fascinate fans.  

https://www.youtube.com/watch?v=a5mZ0R3h8m0