A lot of the time, it isn't simply future restorability. Museums have limited space, and as stuffy and unchanging as they can seem, really do reflect the vision

A lot of the time, it isn't simply future restorability. Museums have limited space, and as stuffy and unchanging as they can seem, really do reflect the vision of current curators. Simply by math, a lot of pieces don't get selected for display, and they just hangout in the archive for whatever scholar/student/future curator might be interested. Additionally, a lot of the art in the archive is by nature going to be stuff that might make sense to display in a dedicated exhibit, but less so in a general museum. By that, I mean that if you have a handful of Picasso canvases, along with 100 of his sketches, displaying all 100 sketches probably doesn't make sense unless you're doing a special Picasso exhibit. In this way, the archive is important, and Rijks burning down would suck. Along the lines of your thinking, however, there is a ton of amazing art sitting in investors' basements and shipping containers that we might never see again, much of which we've already lost track of.