I believe it's 15-30 years for archival storage, if you regularly unspool and respool them to avoid print through.
Re:Backblaze Hard Drive Stats for 2020
by einpoklum on Tuesday January 26, 2021 @01:46PM
(#25919620)
Don't LTO tape drives cost about a zillion dollars each?
Re:Backblaze Hard Drive Stats for 2020
by toomuchtodo on Tuesday January 26, 2021 @01:53PM
(#25919708)
I recommend acquiring them second hand (but validated) for personal use.
SSDs don't have this archival longevity yet, and hard drives are better when powered up and the data is always hot for scrubbing and migrating when indicators of drive failure present.