I have been traveling and then jetlagged/sick during this conversation, but I’ve been following it with interest. I see some are annoyed by it–and it is definitely a bit of a rehash–but I gotta say that one thing I just love about the Zcash community is our willingness to wrestle here in public with important issues. How cool is it that we have a chance to debate? Respect to everyone who is thinking about this, including the haters and the newcomers. 
I have lots of thoughts about ZSAs, but let’s start with the ethos, and then go into more detail about business use cases and other concerns.
Are you here for Freedom Money? Because ZSAs are Freedom Money. Zcash already provides the freedom to transact privately. The freedom to disclose transactions to some but not all. The freedom to save privately. All this freedom, but with one restriction: you must transact in ZEC. That is anti-freedom. True Freedom Money gives people the freedom to transact in whatever currency they prefer. This is not hyperbole; when I talk about red·bridge with anyone outside of the Zcash ecosystem, 99% are concerned about being forced to save in ZEC. ZSAs give an entire new swath of users freedom to save and transact in the way that they would prefer.
Maybe you’re here for number-go-up money though. If you’re here for number-go-up, “encrypted Bitcoin” money, then ZSAs could be seen as bad because it gives users a choice not to use ZEC. Giving them this raw deal–if you want Zcash-quality privacy, you gotta use ZEC–is a sure fire way to increase demand for ZEC while constricting people into making a choice they would not otherwise make. And it also leaves out all of those people whose wills cannot be broken and would rather give up privacy than save or transact in ZEC.
(But can we have our cake and eat it too? Keep reading!)
My personal thesis, and what I tell people when I pitch red·bridge, is that Zcash is on its way to becoming the premier brand for financial privacy. For the older crowd, Zcash will be the “Nobody gets fired for buying IBM” privacy brand. No doubt there will be many choices for private transactions across many blockchain platforms, but privacy is something that you have to get exactly right, and Zcash will be the brand that the world trusts. No compromises. No back doors. No stopping it. It won’t actually matter if other privacy solutions are technically as good as Zcash. Brand is king, and Zcash can own the Freedom Money brand if it wants to.
IMO the “encrypted bitcoin” narrative is overblown. It’s a good origin story for Zcash, absolutely, but it’s clearly full of holes at this point. Bitcoin is ossified while Zcash’s node software literally expires every 16 weeks, and a new version has to be installed. Hard forks happen regularly (as we are discussing right now!). The community is completely open to considering huge network upgrades like Crosslink and Tachyon. This is not Bitcoin-like at all. Zcash is Zcash.
ZSA Use Cases
Some have said in this thread that ZSAs have no use cases. I beg to differ. Pitching red·bridge to investors, I’ve had many discussions about this, and the ZSA slide in our pitch deck always gets the most attention. (As I’ve already mentioned, people want the freedom to transact privately in the currency of their choice.) Not only that, a token launchpad currently on Avalanche has been in talks with us about supporting straight-to-ZSA token launches over red·bridge. Not only that, the NEAR Intents folks have said publicly that they would support ZSAs “from day one.” I’m not sure what Zaki is up to these days (???), but he is certainly wrong about the lack of business interest in ZSAs.
I agree that USD-denominated stable coins, while they would make a great use case, are not yet feasible due to regulatory pressure on the issuers. However, a stable-ish coin such as Ampleforth and other similar projects could work. And as others have mentioned, perhaps DAI is a good fit. Also, shielded BTC or ETH-denominated ZSAs? These could be very appealing. I agree that ZSAs of NFTs could also be potential interesting use cases.
Some have expressed distaste for the memecoin ZSA use case, and I agree personally. They’re scammy and extractive. However, I expect that ZEC has been used, is being used, and will be used for things I personally find distasteful, and we have to decide what’s more important, Freedom Money or avoiding memecoins. I choose the former.
When it comes to use cases, one thing to remember is that in crypto, and specifically with Zcash, we are working with an emergent technology. Insisting that we only move forward when we can see crystal-clear business use cases is a very high bar indeed, and one I don’t think is a good one to use. The internet wasn’t created with today’s business use cases in mind; rather, it was created from a recognition that a fault-tolerant worldwide computer network could probably have usefulness far and beyond military applications. That is enough.
Addressing Some Concerns Raised In This Thread
Sunk cost fallacy. This is a real psychological phenomenon, so it’s worth considering if we as a community are victims. For me, I joined the Zcash community as a builder just after ZSAs had been built, so for me, there are no sunk costs, and all I’m looking at are future benefits–and extremely low development costs. I’ve been waiting for ZSAs to be integrated for years now!
Developer resources. The concern is that ZSAs will take up valuable developer time that could be better spent maintaining security, etc. This assumes a fixed amount of developer resources for Zcash, but this is a fallacy. Please consider this: red·bridge developers have come to the Zcash community in part because of the promise of ZSAs, and because of investor interest in ZSAs, our team will grow. I am not saying that we are as skilled yet as Daira-Emma, Str4d, Sean, and others, but I will say that as CEO, I intend to develop our team’s technical skills to understand the Zcash platform on their level.
ZSAs will attract regulatory scrutiny. My friends, Zcash is going to attract regulatory scrutiny with or without ZSAs. It already has. What will make Zcash unstoppable is its widespread use.
ZSAs will harm the price of ZEC. On one hand, yes, this could be true because users will not be forced to transact in ZEC if they want Zcash’s privacy, so demand for ZEC could be lower. However, the Zcash blockchain can balance this out with specific policies that maintain ZEC’s premier status. For instance: higher fees for ZSA transactions, paid in ZEC. ZEC transactions are always prioritized over ZSA transactions. And so on.
Blockchain saturation. This is a “high quality problem” indeed, but I think it’s my biggest concern about ZSAs. What if ZSAs become so popular that the Zcash blockchain becomes slow, bloated, and expensive? Tachyon will reduce this problem by 100x, but is 100x enough? And what if ZSAs become this popular before Tachyon?
ZSAs will harm security. ZSAs do add some complexity that increases the attack surface, but not by as much as some would think. One of red·bridge’s advisors, a Bitcoin maxi, brought up the very real concern in the Bitcoin community about Bitcoin’s security budget becoming too low due to halvenings. He pointed out that Zcash as-is would have the same problem, but with income from ZSAs, this would no longer be an issue.
In this way, ZSAs would actually improve long-term security.
Onward!