Well, the whole thing is computer data, stored on media. Already these days it's hard to find hardware to read the 5.25" floppy disks that I stored my code on in the late 1980s, and that's just three decades. Preserving digital data is a continuous effort.

And yeah, you can encode your private keys in gold, and I kind of think that everyone should do that, to keep future archaeologists puzzled :-P