Let me elaborate:

The dynamics are really flat. The crescendo at the end doesn’t feel that distinct from the chorus. The vocals don’t have more energy, nor does the instrumentation: there’s just a few more layers. The guitar line through the whole song is simple but doesn’t hook. The drums are just a simple military snare, which doesn’t add anything rhythmically (in fact, they fight with the rap flow during the verses). The strings and keys are just there to drive the basic chord progression, instead of having any interesting timbres or textures.

There’s just an overall lack of individuality in the music. Outside of the vocals, what is there in this song?

Compare to David Bazan’s Wolves At The Door: still relying on relatively simple layers, but the instruments tie together or contrast tonally to heighten the emotional impact. The production isn’t sanded perfectly smooth.