In 343's story we are not, necessarily, descendants of Forerunners which might be why we could be better Reclaimers.

But...

L has been messing with human evolution. Her intent was to make us more suited for the mantle.

But could you trust a Forerunner's judgement on this? Are forerunners tainted? Could we have been tainted with Forerunner sin? What would the Precursors think of the results of her actions? Do they still care about original sin and blood borne, inherited, guilt?

Did her tampering invalidate the Chiefs right to be the chosen one?

And the Precursors plans never did pan out, should we trust their judgement? Are they tainted with loserism?

Or is all that old testament biblical stuff no longer relevant to the Halo story?