I feel like I’m missing some underlying point here, since you’re assuming there is a financial difference between buying, say, 100 gram of gold on the stock market vs having it stored at home.
A HAM radio and the skills to operate it would be worth more than its weight in gold in many disaster scenarios.
The three precious metals for a balanced portfolio. Gold, silver and lead
Not knowing how much this is true, my impression, as a layperson, is that the claims would mean investment gold was more of a financial mechanism that only works because everyone is playing along that it has certain value governed by certain rules. If that's true, I don't know when the rules would stop or change. I decided I'd rather just plow my savings into total-market index investing of US stocks, than blindly guess about how and when gold would help.