>>16499659I'd say it's because of the sexual repression during the victorian period in western europe and then the sexology movement in the late 19th and early 20th. The sexual liberation movement brought sex into popular expression, where more and more people began using sex as a means of self expression which then is presented in music, media, etc.
Now everyone thinks it's such a basic fundamental aspect of the human experience and it's put on an annoying pedestal.