Claiming that the FT is not necessary for digial audio is like claiming that the you don't need the rocket equation in order to build a missile. Sure, its technically possible, and yes, there were probably early pioneers that forged ahead before the mathematical theory was fully sketched out, but our understanding of the fourier transform has drastically increased our ability to design acoustical systems.

Those analog anti-aliasing and anti-imaging filters are designed using LTI systems theory, that fundamentally rely on the Fourier tranform to reason about their transfer functions. The Nyquist-Shannon sampling theorem was proven using the fourier transform. Without the fourier transform, you need to rely entirely upon time domain representations of signals, and perform your analysis using tedious convolutions. You can't use a spectrum analyzer to examine the signal to noise ratio of your CD player. While it's true that digital music could technically exist without the fourier, there is no way in hell it would be as pervasive as it is today.