I'm personally of the view that hosting too many sites will dilute the audience the best and most up-to-date ones receive. This particular site looks very nice, but doesn't offer much (if anything) that isn't readily available elsewhere, on a site that's maintained and therefore, you could argue, deserves more visitors.
Having said that, having a specific "museum" (mausoleum? Ho ho - no) sounds like a good idea, so long as it's clear that sites within it are are inactive and outdated. It seems a shame to let good sites die, and poking around old (embarrassing) sites is always "fun", unless it's your own.