It is, I'd say, implicitly un-American, in the sense that it celebrates a mindset we have -- outwardly, at least -- shunned.
Talking about “fairness” is not a sign of socialism nor is it remotely un-American.
And any lover of “Seinfeld” would regard banning the “Soup Nazi” episode as scandalously un-American.
A term used, primarily by extreme conservatives, to attack principles or practices considered to be at odds with the values of most Americans. Many object to the use of the term on the grounds that it is vague, shortsighted, and intolerant.
Note: The House of Representatives maintained a Committee on Un-American Activities (HUAC) for several years. It was especially known for investigation of alleged communists. (See Alger Hiss.)