Actually it’s more related to the underneath technology itself, that may be considered secured, but it’s not practical for most people.
Services like Dropbox or iCloud can easily be more secure, but they do not offer fully P2P encryption because if people lose they password, they will lose everything on there. Actually Apple did it few years back and they had to back out.
Same for banks, image if forgetting your PIN or losing your card, would make you completely lose your banks funds… it’s just crazy to thing about it. Although it’s still easy to find people with gold or jewels at home, it’s not a common practice on big part of the world, to keep savings (cash) at home.