Apple Leaves iOS Kernel Un-Encrypted for First Time

Does this mean the "cat's out of the bag" forever more? If they encrypt the final release, does that provide any benefit, anymore, or was obfuscation the only benefit of encryption? Did the prior encrypted kernel simply make exploits more difficult to find? Was there any other benefit to encrypting? I assume jailbreaks are more likely (to be frequent) now? Does this mean the federal government is less likely to need Apple's help to break into phones or install their own software? Is Apple now any more worse off than, say, Android, where the kernel has been open all along?

How conceivable is it this was a terrible blunder? Wouldn't there have been safeguards in place to prevent this in their build system, like an encryption step? Or, like whatever stub does the on device decryption failing, and preventing install? Wouldn't they have had to intentionally work around that? And if it was a colossal mistake, will it likely be beneficial in the long run, anyway? (More eyes, more reports, more fixes?)