Elune, the nelf's major goddess, has been described as a pretty powerful deity throughout Warcraft's history.
Nelf's racial shadowmeld comes from her, she blesses their moonwells, mothered Cenarius, and has vague but notable ties to the various powers such as Green Dragons and Naaru, possibly even the Titans given her 'tears' are a pillar of creation.
She's never been depicted the same as the general 'light' or 'shadow' powers, and has even had shades of Arcane in her aesthetic.
But Blizz has been depicting her less favorably since the start of BFA, what could they be planning here? It seems really bizarre to kick the nelfs while they're down and have Tyrande say Elune abandoned them while WIELDING her "Night Warrior" power, so what's the story the writers are trying to lay the groundwork for?