In hi-fi, distortion is NOT a good thing. Full stop.

However, the techniques for reducing distortion, such as the liberal application of global negative feedback, often sound worse than the distortion they reduce. Hence an amplifier with low or negligible distortion may sound worse than an amplifier with higher distortion.

It is for this reason that modern amplifiers have higher measured distortion figures than the 'zero distortion masterpieces' of the seventies and eighties.