The increased audio fidelity of 16-bit consoles brought several significant changes to video games, but perhaps the most important was that instruments could be readily identified. Instead of the melody being assigned to a triangle wave, for example, it could be assigned to a trumpet.
This change, I would argue, brought about a shift in musical thinking. Before the 16-bit era, game composers thought like programmers (“How can I arrange this so that the countermelody will sound all right?”); with the ability to mimic real instruments, they thought more like composers (“Which instrument do I want for this part?”). The upshot was that virtual instrument parts began to more closely resemble real ones; when the audio actually sounds like a trumpet, it feels natural to compose a trumpet-like part.
via Tim Carmody