The only way forward left is through improvements in microphone, headphone and loudspeaker technology. Distortion figures for amps, CD players, DACs, cables etc are already vanishingly low. Even transducers are pretty good outside the bass region which naturally enough imparts greater stresses on equipment materials and structure. Loudspeakers also have still to get rid of the crossover and remain full bandwidth.
As for recording quality, its out there but perhaps just not in the genres we all listen to. If it becomes profitable for the industry to do so then we might see a huge jump in recording quality. If.
After all, if they could do it in the 1950s, then they should be able to do it far better now that 'bouncing down' in digital is infinitely less harmful. I'm guessing that the consumers back in the early days wanted better sound and the industry wanted to give it to them.
After Beatlemania, everything changed. Or maybe it was already going that way already. The era of the voice was coming to an end. Bing, Louis, Frank, Nat, Judy, Doris, Peggy etc were all on the way out. Their recordings will remain forever.