I think we are going backwards in audio solid state wise. The death of the discrete transistor is upon us. All the fabs that used to produce great discrete transistors are now owned by third tier players. Take Motorola, for example. Or Toshiba.
The proliferation of integrated circuits and operation amplifiers has killed the discrete transistor. Everyone waxes about John Curl and Nelson Pass, but most of their designs cannot be built today. At least not on a mass scale. Talk to John Curl about one of his later designs for Parasound, the JC3 phono pre-amp. He wanted to build it with discrete JFETs like his other designs, but was forced by Parasound management to use IC opamps because Parasound believed they could not get an adequate supply at a reasonable price.
There is no question that IC opamps allow simplification of circuit topography and lower costs. But at the cost of sound quality. Like the CD, we have given up quality for convenience in the solid state design or amplifiers.