We had this conversation about ten years ago. Landtuna has his opinion, but the fact is the word “oldie” to describe something from the past goes back to the 1870s (not a typo) and it’s been used fairly continuously in reference to music since the 1940s.
Art Laboe didn’t invent the term when he started playing a heavier mix of past hits on his KPOP show in 1957—-he just gave a common phrase, “It’s an oldie, but it’s a goodie”, a more concise label—“Oldies But Goodies”, which in his case, meant post -World War II “race records” up to and including records that had been on the chart a year before.
Before Bill Drake popularized the term “golden” for past hits (whether they’d gone gold or not), radio deejays and stations called any record no longer on the chart an “oldie”. In some cases, those records were only six months past their chart peak.
In the same way that “Top 40” and “Adult Contemporary” are not types of music, but descriptors of a format in which the music evolves over time, “Oldies” just isn’t a type of music.
In 1972, when the big oldies format boom began with WCBS-FM and K-EARTH, some guys born in 1900 could have said “Nope! Oldies are from the 30s and 40s”, denying Boomers the right to use the label. They’d have been wrong. It meant their music once. It meant our music once. Now it means our children and grandchildrens’.