I'm assuming that's from Japan, from the title.
Both karaoke and impressions of famous people are popular on TV here. Impressions of famous singers by famous comedians/actors etc are even more popular. You'll often see programs where the aim is for someone to absolutely perfectly mimic a recording (measured against a karaoke machine that awards scores on the basis of how close someone gets to the pitch etc of the original recording). Sometimes they are competing against the artist who originally recorded the song and it's amusing how many times the original singer loses to the mimic.
There is, of course, the very Japanese phenomenon of the "otaku". People overseas know the word, but think of it as something purely connected to nerds and anime/manga. But essentially it means someone who takes one interest/hobby very seriously indeed and immerses themselves in it. Plenty of Japanese people like that, devoting their lives almost to one quite narrow field of interest.
So you'll often find someone who knows more about a particular aspect of your own culture than you, or the same for a particular band/genre of music from your country. This desire to faithfully (too faithfully?) mimic a British band from the 1970s is born out of that impulse I think.
Maybe part of that is the Japanese admiration for someone who devotes themselves to perfecting a relatively narrow area of activity, but can as a result replicate that faithfully and perfectly every time as a result. Probably born out of admiration of craftsmen, kabuki actors (where the emphasis is on perfecting the standard movements, with less emphasis on the actor's personal free interpretation) etc.