It's not an entirely analogous situation - for one thing, things have really moved on in terms of storage since those days. The ubiquity of today's DVDs, CDs, hard drives and iPods mean it's going to take a lot longer for all details of their workings to be lost in the mists of time - and in this specific case, the digital masters of blockbusters like Star Wars aren't going to lie dormant gathering dust in a basement for 50 years. Even barring George's own oxymoronic brand of perfectionism, they'll be seeing constant use (and constant copying to the latest medium) for decades, if not centuries, to come. If NASA's tapes had had the same kind of use, I'm sure they would have been transferred from tape to disc to hard disc to DVD-ROM over the years.