The bottom line is the vast majority of people don't really care enough about sound quality to embrace something like SACD. Think about it. Where do most people listen to music? In their cars! SACD is superior to conventional CD, but I suspect less than 5% of the population has equipment good enough to appreciate the difference.
Sony should also be blamed for the way they marketed SACD. In the early days of the format most of what they did was reissue titles that already existed on CD, in many cases LP as well. SACD has the capacity where Sony could have combined two titles one on disc, for a one disc price. Instead they release Walter's Brahms Symphony #4 all by itself and charged $20 for it. Why didn't they put the third symphony on the disc as well? Why didn't they offer bargin pricing to get the format going? They sure weren't having to pay big licensing fees! The Mercury classical CD issues got it right. They added more music, in most cases, and didn't limit themselves to the exact same form as the original records. Why should they, CD has about thirty minutes more capacity. Mercury used it to their advantage and charged a low price. Sony could have filled up the entire disc with music and charge $12.99. Instead they chose to gouge the early converters.