[nootropicat]

>Clearly, optional privacy is not privacy at all.

This is a marketing term without actual meaning. There's a system with some anonymity. Then there's the external world. There's no 'optional' anonymity. The error lies in incorrectly comparing monero to zcash as a whole, instead of shielded transactions themselves. Names themselves are irrelevant. Depositing xmr to an exchange is equivalent to withdrawing from the anonymity pool.

From the design perspective, the mixin model is vulnerable to an active adversary that has spent output data from exchanges and spams the chain to generate recent known outputs when the target makes transactions. Full zk-snark anonymity is fully resistant to this.

A problem of both xmr and zcash is that they have no other use than anonymity, making it easier to ban and impractical for larger amounts and forcing commerce to hedge price risk, generating deanonymizing metadata. For actual commerce anonymous dollar is the ideal, for as long as dollar remains the main unit of account in the world.

https://zk.money supports dai, although it's still in alpha with a limit of $1000 per external deposit.

https://aztec.network/index.html