And this is the problem with “trustworthy claims on gold”… you need to trust they won’t be confiscated by authorities. You have not only add a third party as issuer, but self-inserted fourth parties all along the way.
Also, 1930s Germany might disagree that your personal safe is all that safe. Either way, though, it’s certainly one or two orders of magnitude less safe than the same amount of Bitcoin, which can fit in your brain or be teleported to the other side of the world at the push of a button. Or can require 3 of 5 signatures to move, etc etc