CD/DVD writables - 5 years is all you can count on at best, after that you are on borrowed time.

External HDD about the same

Memory Sticks about the same.

moral - we have been chasing capacity and price for a long time, not durability.

With tape we did not think nor were aware of the lifetime limitations back then. I have seen CDRs at about the price of a coffee that are guaranteed for 100 years. But can you wait to prove it?
The music industry used VHS cassettes (digitally encoded) and are now paying the price. Decca developed their own system on reel to reel video tape and suffered less over time.