one could argue there was a kind of bubble of the American middle/working-class from say 1945 through the 80's/90's. and that this bubble has been deflating sin

one could argue there was a kind of bubble of the American middle/working-class from say 1945 through the 80's/90's. and that this bubble has been deflating since, through a combination of Mexican labor immigration (both legal and non), off-shoring of jobs to China/India/etc, and the increasing automation of software and hardware whose benefits disproportionately flow towards the capitalists and the highly technical specialists like programmers. That would be a kind of bubble which lasted a half century. Period where that segment of American was "over-valued" relative to otherwise comparable people who happened to be born in other countries around the world.