Seventies
Seventies
Cueball: Nice jacket. Hey– Cueball: The seventies called. Out-of-panel: Oh? What'd they want?
[Cueball looks at his smartphone, holding it in his hand.] Cueball: I don't know. They didn't leave a message. Out-of-panel: Weird.
1974: [A person in bell bottoms, who has no jacket, looks at a rotary phone receiver.] Voicemail service: If you'd like to leave a message, press "1".

This is a take on the common insult "<year> called and they want their <item> back", used when one is wearing something out of fashion (used before in 875: 2009 Called ). In this case, the comment is literally true: someone in the '70s called, but did not leave a message. Instead, the caller is puzzled because answering machines and especially voicemail were rare or nonexistent in the 1970s, and his telephone has a rotary dial , rather than a touch tone , so he can't "press" 1.
The caller is wearing flared ("bell bottom") trousers, which are frequently associated with 1970s fashion. The caller is somehow using time travel to directly dial a number in the present.
Originally telephones had rotary dials instead of buttons, hence the origin of the terms "dial tone" and "to dial a number". Touch tone phones were introduced in the 1960s, but weren't standard in many places until the 1980s. Rotary dial telephones used pulse dialing to transmit numbers and push-button telephones use DTMF (although phones from the '80s and '90s could often use both). Modern voicemail systems regularly don't support pulse dialing, so even selecting "1" on the rotary dial would not choose "1" in the voicemail menu system.
The title text plays off the fact that the telephone had not yet been invented in the 17th century: in fact, all of the component technologies, including the materials used for the casing, were unknown at that point, and therefore the telephone is assumed to be supernatural in origin ("demonic... ſorcery"). Randall uses the character "ſ", the long s , which was used in written English to take the place of the modern lowercase "s" in the beginning and middle of words. It was phased out around the beginning of the 19th century.
Cueball: Nice jacket. Hey– Cueball: The seventies called. Out-of-panel: Oh? What'd they want?
[Cueball looks at his smartphone, holding it in his hand.] Cueball: I don't know. They didn't leave a message. Out-of-panel: Weird.
1974: [A person in bell bottoms, who has no jacket, looks at a rotary phone receiver.] Voicemail service: If you'd like to leave a message, press "1".
