They say history is written by the winners, but when it comes to technology, history is written by Americans. MiniDisc was a huge success for Sony, and was the winner of the tape-replacement format war in virtually every country - except the USA. It was so successful that Sony is still making blank MiniDiscs today. (Though they are not sold there, Americans can type MDW80T into eBay if they'd like some brand-new Mini…
Minidisc was a HUGE commercial flop, with a paltry number of releases. It found utility in some pro audio racks but in no nation did it ever come close to replacing DAT in pro audio applications, or cassette tapes for music copying or distribution.
What I remember from my minidisc days were that at least the ones I owned were all recorders. Even though I bought zero minidisc albums, I had a few minidiscs with albums recorded from CDs.
Even though minidisc wasn't ubiquitous, I'm not sure that the number of releases is a good measuring stick.