The cost of security for gold is high, but only for the big shots (banks, etc.). Normal people can keep quite some value of gold with minimal volume, e.g. 1kg (>60K$) fit in a cigarette box. Enough for most to keep some value for after a crisis. Because that´s the real value of gold. If everything breaks away, even the internet, you can use it to increase your chances to survive (this and a fair amount of weapons plus ammunition if it gets nasty). In a real crisis crypto gets useless.
That is a good point decentralized gold storage basically could cost $0.
Just a backup hedge sitting in a drawer.