Some people don’t want some gods that have traditionally been only/mostly found in one race to get expanded on to a ton more races, as it can feel like the uniqueness of the god and race is watered down.
Elune was first a nelf only diety and the night elves was her chosen people, then added a version of Elune to the Tauren, then it’s just kept expanding to trolls etc, and now even fully new and unknown planets.
Same reason some people got pissed that the Loa Bwonsamdi had made deals with non-trolls. Since the Loa are beings that’s worshipped by the trolls and the trolls are their chosen people to be worshiped by, sure some have additional races like tortollan or sethrak, but they all have troll worshippers and the races in question have close ties to the trolls. So when something so unrelated like a gnome makes a bargain with a loa even if it makes sense lorewise, then it will feel wrong for some people as it’s so far removed from what it usually is and has been so far.