The term AM pop tunes is a bit of lost term.
I've never actually heard an AM pop station. At least here in California, the only AM stations I've heard are news, sports, talk radio, and Spanish. Maybe a classical or an oldies (1950's) station.
But as far as the so-called traditional AM pop station, I've never actually experienced one. All the pop stations switched over to FM a long time ago.
AM broadcasting now attracts mainly talk radio and news programming, while music radio and public radio mostly shifted to FM broadcasting in the late 1970s.
But as far as I know, the term AM pop radio means really generic bubble gum pop music.