Perhaps one form of legitimate "guilty pleasure" could be where the listener enjoys certain aspects (say- a rhythm track) but dislikes others (say a chord progression in the same track) as such there is a certain cognitive dissonance as they listen to the piece between the elements they like and dislike *at the same time*... take for example a pop garage track where the chords seem too wrote, obvious and over diminished (in a technical sense) and played on an overly lush Rhodes sound... but at the same time the percussion is a slippery, syncopated beast with amazingly crisp and defined snare sounds... however it might be more accurate to describe this as a kind of musical self-doubt as you listen, rather than "guilty pleasure" (which obviously presumes "guilt", ie- a certain self-reproach for supposed inadequacy or wrongdoing, which presumes some kind of musical law of taste...)
ahh now you're onto something as this seems to be the opposite of the kind of thing that's happening now, the crisp and defined snare sounds are thrown out and the cheesy wailing diva and overrought rhodes chords are the bits being kept,
so its ok to do a punky cover of better off alone by whoever it was, typically melody being more important to rhythm things get celebrated simply because they are tuneful in that respect. Maybe thats the only current aspect of this transition and its not really as radical as it threatens to be, but then you get someone like dubstepper d1 doing a version of 'you're not alone' by olive, it's a lovely tune though isnt it?
it's a weird kind of exploration.