Not so much a “composer”, but the type music I disliked and loathed the most before all others was “easy listening”… anything that was in the direction of Lawrence Welk or Ferrante & Teicher or Bert Kaempfert… you know the style… and that included most of Mancini’s soundtrack albums of the day and what not. When I seriously started listening to music as a teenager, you could give me Stravinsky, Ligeti, Boulez, Schnitte, anything with thorns and spikes, but if you gave me “easy listening”, and you ensured my disdain.
I’m much more mellow about that type of music nowadays and can take it for what it is.