TOTP - Top Of The PopsThis BBC show started life in 64. It focused on the top POP songs of the day. First show featured:The Rolling StonesThe BeatlesThe Dave Clark FiveThe HolliesDusty Springfieldand othersThe point here is POP music is just that ... what is popular of the day that pushes the creative and technological envelope. Rock and Roll, Classical, Jazz, whatever.
I'm not arguing the definition back in the day but that's not the definition NOW!!