I guess you could say the same thing about DVD-A, except there's not as many people with collections to sell so it's not so noticeable. :~)
While I think the hi-rez medium isn't likely to replace the CD, either as SACD or DVD-A, I'm very happy to keep getting SACDs as a niche format, much as I am with vinyl; in the classical music area there are more than enough new quality releases to keep me satisfied. So I'm not giving up my SACD player any time soon.