People got too fascinated by the shinny colorful reflection of CDs.
And then later on even more fascinated with the production of all black cd's etc. To be honest, I like those as well, probably just beacuse it's something different.
And yes there's something to say for the sturdyness of MD and the 'openness' (almost open-source like lol) of tape.
Tapes can go too. Depending on the binder the tapes have to be baked to restore them. (Video and audio tapes may suffer from this).
When CDs came out people really liked them. They sounded great and didn't involve the care needed with records or tapes (cleaning records and tape pinch rollers... ug). You could skip to any track without flipping it over. Minidiscs came out many years after cds. Records probably are the most archival since its music in physical form.