The wording does imply this, but since the whole point was to free the human from reading all the details and relevant context about the case, how would this double-checking actually happen in reality?
That's your assumption.
My read of that comment is that it's much easier to verify and approve (or modify) the message than it is to write it from scratch. The second sentence does confirm a person then modifies it in half the cases, so there is some manual work remaining.
It doesn't need to be all or nothing.
On the off chance it’s not for that reason, productivity requirements will be increased until you must half-ass it.