BTC does not eliminate the need for security. The USB in question would need military grade security, and the exclusivity of the claim of its holder over the ledger entries recorded in it would never be demonstrably secure, because BTC's value is information that can simultaneously exist in multiple locations.
The article reads like a high school term paper. BTC is a fiat currency whose scarcity is determined by the actions of some random computer programmers who, for now, aren't leveraging that power for their own personal benefit. Gold is a natural element whose scarcity is a function of the laws of nature, and there are no people today who can measurably exercise their own power to reduce its scarcity.
Also, not to nitpick, but a single gold bar also could theoretically have value equivalent to the entire BTC Blockchain. A single dollar bill could too. This would be the case if BTC was valueless. The article isn't very well reasoned.