Not quite true, Stephen's (edited, thx) first solo was released in HDCD. A dead format now in newer AVRs, yet I still think it sounds MUCH better than redbook CD. Unlike the CSN&Y DEJA VU in HDCD (Japanese, which goes for three figures!), it is relatively cheap and available.
Joni Mitchell's HDCDs are well worth collecting, and of course the Grateful Dead released a box of all their albums on HDCD. Here's the Stills HDCD listing on Discogs.com:
https://www.discogs.com/release/1917301-Stephen-Stills-Stephen-Stills