Nothing protects your other examples from corruption.
> why choose one of the most corruptible and corrupted approaches?
Because when the non-prophetic elements of it are applied to life, all of the anxiety, fear, and dread you feel evaporates. It's only when you view it through the lens of a "church" or "leader" (read: group) that it loses its meaning.
I've read the I Ching and it lacks a religious/church element which leads to the conclusion you've had. It's not until people take it and turn it into something it isn't that it loses its value.
Arguably, Christianity, due to its claims, has become weaponized. Interestingly, this very outcome is prophesied in the Bible (which, personally, cements my faith in it what it prescribes).
As does the I Ching
These are all just Rorschach tests, why choose one of the most corruptible and corrupted approaches?