In many instances a very neutral piece of equipment will expose deficiencies in a system. Someone with a system that is too "hot" will prefer a DAC that is rolled off.
A neutral system (flat frequency response curve) will sound too hot (sibilant) at higher volumes. This is why Loudness Compensation was so popular.
Most of the audible problems with stereos are issues of amplitude or frequency response. It only takes 0.5 dBFS at any given frequency between 100 Hz and 10 kHz to make an audible difference in sound quality. I think what we tend to do is compound errors to achieve a curve we like. You can accomplish the same thing with digital EQ and if you measure your system after you have achieved the sound you like you will be able to adjust your system to any component. This is called a target curve.