Why redbook over SACD?

The issue might also be a response to the market.  Redbook CD has rebounded to respectable sales levels whereas SACD seems to be an ever shrinking format.  Clearly Sony should have opened up this format when it was first introduced.  It is a shame, but it is what it is.  Technically too, the early limitations of Redbook seem to have been largely overcome and this fact has definitely given the format reconsideration.  If anyone from Sony is listening in, it might not be too late as there seems to be a demand in the market for premium sound quality.  HIREZ does not fill it.  Vinyl can, but to do so requires extraordinary dedication and expense that only the most dedicated are willing to undertake.  Redbook CD reaches, but doesn’t quite scratch the itch even at it’s current best.  So, SACD struggles on, but it is so very limited in scope at this time that it just is not what it could be or should be.  Sony, is anybody there?  Are you listening to us?

cos SACD adds nothing. if Redbook is dereived from a master that is excellent, SACD is just a needless pain

everyone is right!

I believe it has more to do with the transport mechanism. All things being equal a purpose built mechanism that is limited to Redbook only can potentially do a better job playing Redbook CDs than a SACD capable mechanism can do when playing Redbook CDs.

The issue might also be a response to the market.  Redbook CD has rebounded to respectable sales levels

That’s just completely untrue — CD sales are down 97% from their 2000 peak and are bumping along at 33 million units comparable to what they were in the late 80s, and even vinyl is far outselling CDs at this point.  From RIAA data…
 

Physical sales dipped in the first half of the year, with vinyl revenues down 1% and CD revenues down a sizable 22.3%, so that physical revenues at large slipped 5.9%. Vinyl now significantly outsells CD, with vinyl shifting nearly twice as many units and generating more than four times the revenue. Total vinyl revenues for January to June were $456.9 million, while CD revenues were $108.1 million.