This is true. The problem is bad actors can use this to bypass Apple's review. As an iOS app publisher I slightly regret this inconvenience. As an iPhone user, I appreciate Apple looking out for my security.
It's much like the argument 'if you ban guns only criminals will have guns' and it's quite true in this case.
it's about damage mitigation, and shutting down a 3rd party "app-hot-fix" service is a good move.
it's harder to fool only apple, than to submit some naive looking thing and still have unmitigated access to changing its code.