They aren't. Zcash has opt-in privacy, which I think we've established doesn't work. By this logic BTC also has opt-in privacy – just use a mixer. Well, except that your BTC will be tainted if you do it, which effectively makes BTC non-fungible for all intents and purposes.
The only way to have a private, fungible cryptocurrency is to make privacy mandatory and not "something you enable because you are a drug dealer". Does this mean that everyone using Monero is automatically a drug dealer? Even if it does, it's waaay better to have consistency vs having a cryptocurrency partitioned into "normal coins" and "darknet market coins"
I think it's more useful to think of ZCash's featureset not as privacy defaulting to on or off, but as giving you the option to have pseudonyms.
If you were running a non profit and you wanted people to be able to anonymously contribute to it, but you wanted to prove to your anonymous donors that all of their donations were being spent in accordance with the goals of the nonprofit, you might use ZCash transparent vs shielded addresses as a way to create that division between transparent and opaque.
As for t-addresses having been default, that's a regulatory hack. Exchanges have a better shot at being compliant if they can use the chain as a source of truth. So t-addresses let them create a space where they can do that, and then you as a user can privately move funds out of the exchange's domain and into a black hole without having to get your hands dirty with some other exchange.
Yes I know that monero let's you generate keys for this on a tx by tx basis, but it's not the same. It's just different privacy properties with different use cases.
Monero, however, has the objectively superior CLI. It's fantastic.
You could just as accurately say Zcash has opt-out privacy too. And the privacy is much more than a mixer since you got ZKPs.
Opting out of privacy gives it more plausible deniability, which is why you can find it on coinbase. Not that you should need deniability, since no one has any business knowing what you're doing with your money.
> Opting out of privacy gives it more plausible deniability
So if you actually want to interact with the real world, you have to opt out of privacy? And if you enable privacy you are automatically treated as a weirdo? I don't get the whole point of Zcash.
It's the same issue as with Bitcoin – you can make your transactions private, but it's not the default and not obvious for new users, and anyone who does it is subject to suspicion.
It really looks to me like this "privacy" aspect of Zcash is just a marketing gimmick. It doesn't have any advantages to just using Monero in the first place.
Shielded by default or opt in depends on the wallet you use. As you can imagine, a lot of people like shielded by default. There are reasons to have transparent transactions btw. You may want public proof.
Again, it is not the same as bitcoin. Using a mixer does not come with ZKPs. The transactions are also still public. You can see how much was put in and how much was taken out. Worse, you now potentially have traceable tainted coins and a target on your back.
The point of Zcash is the Z. Zero knowledge proofs. Monero uses differential privacy. Zcash has much stronger privacy guarantees.
