For large valued transactions, I believe Zcash's technology will ultimately win. It has the largest anonymity set which can't be practically spammed, because the anonymity set is every coin and every transaction that can ever be done.
That would have been true if ZEC didn't screw it up and made anonymous transactions compulsory, instead of an option.
I underlined "technology", not any specific coin's implementation (and its design choices). Meaning I think the technology will win. I have no opinion about which implementation of the technology will win.
Afair, there are some issues around a view key in Zcash's technology which apparently Cryptonote/Monero may have some advantage in some cases if that feature is needed. But I haven't studied that issue in depth, especially not lately. I do not know if that is what you are referring to. Any way, I don't want to go off on that tangential discussion at this time. It isn't important to me right now.