I grew up when the CD was king. And I'm seeing it come back with kids now! But I don't think its anything more than a fad. Here's why:
Vinyl has made a comeback. I've jumped in on that trend. I think it's really cool to have this super-old and visceral technology. It makes me happy. But its impractical as hell.
I've seen indie bands in the 20-teens release their music on tapes. I'm sure it was mostly a gimmick. Audio quality on tapes notoriously sucks.
I've seen my teenage niece show me her CD collection with pride. CD's don't have audio quality problems, and they are certainly far more portable. But at the same time, its still just a new fad. They will always be cool from a perspective of nostalgia. Though both my cars still have CD players... it's due for death.
Why? The obvious answer is streaming, but the real answer is digital files. They are just too practical. I feel that the MP3 player must make a comeback, and it could beat the music streaming giants. It has to!