Where is the shame in the rough draft?
I just don't see what the big deal is if, after an artist dies, someone dredges up a painted-over picture, or pulls up a photographic contact sheet, or reveals revised drafts of mediocre stories, etc.
One can assume that most knowledgeable and sympathetic viewers (or readers) would have the intellectual capacity to distinguish between what is obviously a work in progress, or an abandoned work, and the "final cuts" of an artist's output.
Where is the shame in the rough draft??
Granted, personal correspondence is a slightly trickier issue. If the artist is still alive and someone (a former lover? former confidant?) chooses to "expose" or sell or publish a trove of private letters, that does, I believe, cross the line. The seller, in my mind, should know better or have more scruples.
Wasn't there a recent case where a former lover of J.D. Salinger sold off a bunch of his letters? That's sort of low.
But, if the question is scholarship about a prominent writer/artist who is dead, then I remain firm - it's all fair game.