@hagbard I wondered the same so I looked it up and found this:
"Though the fourth season of 'American Horror Story' is set in 1952, the show has bent time to feature modern music. So far, Jessica Lange has performed David Bowie's 'Life on Mars?' and Lana Del Rey's 'Gods and Monsters,' while Sarah Paulson sang a silky-smooth version of 'Criminal' by Fiona Apple.
The bizarre use of music written decades after the 'American Horror Story: Freak Show' setting delivers an added creepiness to the series, with Nirvana's 'Come as You Are' acting as the latest example."
Shout by klukaBlockedParent2016-02-04T02:10:44Z
So they place this season in the 60ies or something but then they let the character play Nirvana on stage. Yeah, right...