As things now stand, it is practically impossible to discuss zero-knowledge proofs for Bitcoin without discussing the technologies and the real-world experiences from the premier ZK proof privacy altcoin. I will not self-censor to avoid knee-jerk reactions: That would prevent me from discussing my longtime dream of having ZK proof privacy in Bitcoin. I have been wanting that since around 2013, according to my recollection of when I first heard of Zerocoin.
Just equating Zero Knowledge Proofs to zcrap here is a disingenuous argument, in your continual context you act as though Zcrap led the way when in fact ZKP has been used forever and it is essential to any privacy algorithm.
With that being said there is ZERO reason to bring up that shitcoin when trying to discuss ZKP.