This phrase is a derogatory saying that usually denounces someone's style in something. "X" is usually replaced
with a time
period whom the person's style reflects. "Y" is replaced
with the item
being made fun of or denounced.
Another permutation of this saying is more common on imageboards, messageboards, and forums. china called...
Examples of X Called, they want their Y Back...
Hey, Justin Bieber
called, he wants his singing skills back.
Hey, the 1970s called, they want their clothing back
called, he wants his hair back