Green’s Dictionary of Slang

1. (orig. music business) catchy, simplistic pop music aimed spec. at the pre-pubescent and early teenage girl market, all, allegedly, prime consumers of bubble-gum; by ext. anything considered frivolous, banal, unimaginative, tacky.

1968		‘Hy Lit’ Hy Lit’s Unbelievable Dict. of Hip Words 6: bubble gum and popcorn music – Top forty sounds which are on the square side; they have no soul or inspiration.
1983		K. Hudson Dict. of Teenage Revolution 30: Bubblegum. Exceptionally banal teenage pop music.
1988		N. George ‘Bobby Brown’ in Buppies, B-Boys, Baps and Bohos (1994) 85: Using funk vocals and hip hop attitude, he ripped right through New Edition’s bubble gum.

2. nonsense.

1975

L. Rosten Dear ‘Herm’ 137: This is not logic but Bubblegum!