> The problem is that this requires people to be constantly pro-active about where they store things, which most people aren't or don't care about right now.
Also, the solution requires you to have enough free cash every year. Data usually can last over long periods of unemployment, and there's the temptation to think that "hell, still I have those keys on me, I can live without that safety deposit box for some time, until I have spare cash"...
More off-grid, less failures. Private safety deposit box companies are excellent.
Banks aren't as discreet as private vault companies and it's not at all unlikely that a government entity would subpoena for your box contents.
Certainly a private vault company could be subpoenaed, as well, but for that to happen a prosecutorial or other undesirable entity would need to actually know you have a box there.
Set the box up, making as-few-as-humanly-possible trips to it, pay for it in cash for years in advance.
One caveat: I would use a bank vault for items like passports, documents, heirlooms, etc. Things that have no potentially-incriminating value or that government would have anyway (passports, DL copies, SS cards)
