First off, no writing of JRRT's begs more fore a rigorous revision than his ridiculous description of
Ungoliant, who just keeps growing and growing - even though her darkening of
Valinor with vapors to a degree that she foiled even
Tulkas and
Manwë was such a titanic effort that it should have shrunk her to a size that would fit into the average
Hobbit's hip pocket. Christopher
Tolkien himself acknowledged his father's occasional tendency to hyperbole, which reached a Taniquetil-like peak with his writing on Ungoliant - and went unrevised in later more sober moods, as so much of the early writing.
Then, Ungoliant never even touches
the Silmarils. What they did to
Morgoth,
Carcharoth,
Maedhros and
Maglor at the end - and very likely Ancalgon when
Eärendil knocked him out of the sky - speaks volumes.
And often, when beings JRRT at least hints at being
Maia spirits taking a specific bodily form, like Thorondor, or the "boldogs" mentioned occasionally, being lesser
Maiar taking shapes like archaic
Uruk-hai, when they breed, their offspring do not inherit their primal characteristics. Even with
Melian and
Lúthien, while the latter among
Elves is at least a notch above even
Fëanor an
Galadriel, she does not inherit her mothers primal capabilities. So while Ungoliant hated light, and lusted to devour it and turn it into darkness, her descendants also hated it, but now feared it.
Well, my rationalization of the matter, anyway.
