This excellent article (History Disappears in a Digital Black Hole) from Scotsman.com shows exactly what I was talking about back in this post on paper vs electronics. Information on the web is far from permanent. In fact, in many ways it's much more likely to disappear completely than information written on paper.
Yes there are ways to back up information, but data storage methods must be kept up to date. Like I said in my post linked above, you can transfer information from tapes to floppies to CDs to the Cloud, but until it's on paper it's still just electrons or magnetic fields. It's not directly readable.
I never like to rely on technology too much, and anything important gets printed as a hard copy. It's also why I like to keep old planners and diaries, as a permanent record and reference.