This response is reductionist. It's like saying "a gun is a gun, so when you hike in the country just carry a 22 with you. Shooting a bear is shooting a bear, right? No, not right. Math is not just math. Not all cryptographic functions are equal. Bitcoin keeps the coins secure in a number of ways. Being able to transparently audit the ledger is a powerful tool. It's a tradeoff for privacy of course, but that tradeoff was intensely debated in the early days. There are other things that get compromised by mixing cryptography into the transaction's inputs and outputs, it's more than just auditability you sacrifice for your privacy.