Entirely this. I do not trust devices to always be working or on my person. I will only use this if I can generate an offline, perfect fidelity backup of my codes.

“But it’s safe in the Google/Apple/Microsoft cloud” is not an acceptable answer.

Someday, we will have brain reading technology to extract information from a newly dead brain, like we have to extract it from a RAM that was just turned off https://en.wikipedia.org/wiki/Cold_boot_attack

Coincidentally, we can also pry fingerprints from your cold, dead hands.