I've been doing a fair amount of research into Zcash and Zero Knowledge Proofs as a concept, and one thing that has repeatedly crossed my mind is that none of the articles or academic papers I've read seem to go really in depth into the negatives of ZKPs.
As far as I can understand, one of the biggest downsides is the computing power and time required to create a shielded transaction, averaging about 40seconds to generate a transaction. For a commercial application on a large scale, this seems unsustainable, especially if you compare it to the concept of creating private channels for transactions between specific parties.
I'm also curious about the regulation implications. ZKPs are often touted as a solution to the problem of financial services requiring some level of data privacy for transactions while still trying to take advantage of the network effect of blockchain tech. But from a regulators perspective, how does this play out? If a company or organization is being audited, is it entirely within their control what transactions they will allow a regulator to see? Consider a private, commercial implementation of the technology that would shield transactions from participants not directly involved in said transactions - is there a way to provide a sort of "god view" to an organization responsible for overseeing these organizations (think the FCC and banks)?
TLDR: What are the regulatory implications of commercial implementations of zero-knowledge proof protocols? Performance implications? Comparison to channels?