Definitely not an oversight because they fixed Death and kept ours the way it is (to the point where they made it abundantly clear in the FAQ). And it works with the tide aspect that with a Leader behind them who has single handedly escaped a God, killed three Greater Daemons and championed the end of the civil wars that those in front of him would be inspired to do great things.
From a non fluff perspective, it is also quite necessary for our army to get anywhere near top tier, we require this ace in the hole to be comp efficient and even then as many have said, once you know how to play against it, it is nowhere near as threatening as it sounds.