You can do exactly the same thing with gold, i.e. holding it in different banks in different regulatory districts. If your friend's house is burgled or burned down. The one advantage of Bitcoin in this respect is that you can back it up in case of disk failure, house burning down, etc.
That's different than using Shamir's Secret Sharing [1] to split the private key/seed across multiple safe deposit boxes.
If one safe deposit box full of gold is stolen, that portion of the gold is gone. If a safe deposit box containing 1/5th of a Shamir's Secret Sharing secret is stolen, the secret can't be reconstructed by the thief, but can be reconstructed by the owner if they still have access to 3 of the 5 pieces (for example).
You can at most hedge against losing everything at once.
It also seems weird to hide a piece of gold at a friends house. Now you expose them to the risk of burglary, as well as to the temptation (in a crisis).
