Everything is debatable, but not necessarily. Kpop fans often don’t debate the technical or engineering aspect of music, but rather if they like the overall vibe or sound of it and this aspect is subjective. Unless a Song is a complete disaster when it comes to the mastering (which would be bad as in bad quality) everything is up to your own personal taste.
And let’s not start with Lyrics cause the vast majority of Songs that hit it big aren’t that deep. It’s often these 3 topics… love, self-empowerment or feel good vibes.