In real life, people don’t often say, “I’m right. You’re wrong,” or, “I have the power here and you have to do what I say.” Rather, people jockey for control or authority in arguing over small, seemingly banal things. 

This conversation between McMurphy and Big Nurse Ratched is not AT ALL about music or pills. Rather, it’s about who is in charge of the hospital — the patients or the administration? In this scene, despite McMurphy’s best efforts, the nurses maintain the upper-hand, even using subtle humiliation to get him to back down. 

If you need a name for this kind of subtext, maybe it’s superiority subtext.