The verse points to the courts of Zheng and Wei, where the old ceremonial music was traded in for something easier on the ear and harder on the mind. Pulled in the context of studies, the stick is asking you to look honestly at what your learning sounds like right now. Highlight reels at 2x speed, cram sheets the night before, the YouTube explainer that promises a whole topic in twelve minutes, the group chat where someone always has the answer. None of these are evil on their own. The warning is about what happens when they replace the slower, drier discipline underneath, the way the old states replaced their ceremonial music one pleasant tune at a time.
Notice that you probably already know which of your study habits are the corrupt court music. There is usually a subject or a paper you keep circling without actually sitting with, and a method you keep choosing because it feels like progress more than it produces it. The stick is reflecting back the small dishonesty in that gap. Drawing 下下 here is not a verdict that you will fail; it is the verse putting a hand on your shoulder while you are still early enough to change the rhythm. The harder, plainer work is still available to you. The question is whether you pick it up before the exam picks it for you.