Simply, different file formats will replace .mp3.
As long as there's a demand for QUALITY over any intensive examination of the content, there'll be "improvements" engineered as solutions. It's not unjustifiable, it's simply that it's seldom necessary those improvements even exist, given that the relative amount of high-quality content doesn't improve quantitatively, especially content that CAN'T be distributed without those improvements.
Truly great music, great visual art, etc. will ALWAYS be made, the overwhelming sea of what is NOT pounding true quality through the noise floor is the impediment.
Arguably, we might be able to generate the kind of mass culture we have without high-speed protocols using different network architectures (they've been around since the 1940s with the advent of digital computing).