$ZEC The current biggest challenge is falling into a dilemma of "unclear explanation":

1) It’s unclear whether the Orchard privacy pool has truly suffered a "hacking attack" over the past four years, and even whether the so-called "infinite mint" backdoor constructed by its team can be proven;
2) Assuming it was indeed "attacked," it’s unclear how hackers within the Orchard pool double-spent ZEC to steal real value, because passing the Turnstile total verification only indicates that they can quietly "consume" it little by little, likely using fake ZEC to purchase merchants, VPNs, gift cards, and other real commercial services. This hidden damage isn’t as obvious as massive coin thefts, but it essentially overdrafts the value that all ZEC holders should enjoy;
3) Even if Shielded Labs is about to announce a new upgrade with a new privacy pool and enhanced Turnstile accounting and cryptographic proofs, it can only prove that the effective supply of the current Orchard pool is less than the total amount entered, and it’s still unclear whether potential vulnerabilities will be discovered in the future, because there is an inherent contradiction between verifiable supply and privacy black boxes. This directly damages the trust built over years in Zcash’s privacy service market. "Privacy" itself isn’t the problem, but "verifiable supply" has become a deadlock for ZEC;