

I can’t address the entire reply since it’s 3 in the morning, but I just want to point out something.
I’m not a communist. I’m not a socialist, or a Marxist-Leninist. I don’t consider myself to be a “leftist” (which I see as an overly broad term), and I’m sure as hell not a centrist. If my views are inconsistent, it’s because I don’t follow any single doctrine.
Magnetic tape. It’s one of the better long-term offline backup solutions. It is compact, inexpensive, has no moving parts (bearings, motors, reader heads), no scratchable surfaces, and can last for decades in a moderately climate-controlled room.
Just keep it away from magnets… or iron vaults. According to an anecdote (that I can’t find right now), a large bank vault was repurposed as an offsite backup storage, except it kept wiping the magnetic tapes because the thick iron walls reacted to changes in the geomagnetic field.