> Drive were quite a bit different in 1996.
Exactly.
It's not available as a commercial recovery service now, and I doubt it's practical with readily available consumer grade technology, but that's not relevant for long term security. It's an entirely plausible process that's just going to get easier with time, and if something still needs to be secret in thirty years it probably won't be. Security isn't always about "can't read this for now", sometimes it's about "can't read this ever."
56 bit DES keys used to be considered secure by some people because an impractical quantity of effort would be required to crack them. That's no longer the case, and it doesn't seem reasonable to assume that just because it's still hard to read faded bits from a 1996 era drive that it always will be. I bet I could pick the erased bits off the 14" 1979 era platters hanging on my wall with a magnifying glass and tweezers. ;-)