Come on. You know, and I know that a backdoor would have been sealed long ago, if it had even a chance of existing. ZCash had, and will continue to have a bright future.
Sealed by who? There are very few people outside of the Zcash team who could even explain how ZK-snarks work, let alone review the code for backdoors. Bitcoin was built with well understood cryptography, and there were still serious bugs many years in. The best well known one was in August 2010, when someone found and used a number overflow exploit to generate 92 billion Bitcoins. Obviously, it was fixed, but my point is that if something like that can happen in Bitcoin, which as I said uses well understood cryptography, you'd have to be naive to think that it couldn't happen in Zcash.
The cryptography used by Zcash is so new, and so complex, that it would be trivial for the Zcash team to place a backdoor without anyone noticing it. And given that several Zcash team members have made statements supporting backdoors, I think it's a near certainty that such a backdoor exists.
