I never said it made sense. Objectively, Void Elves are not ideal high elves due to the remaining differences which prove they are still Void Elves rather than ‘two races mixed up together’. It’s up to Void Elf players who wish to be high elves to rationalise it. That’s part of the roleplay.
But the differences are minute enough that roleplayers should be able to suspend their disbelief and, well, roleplay.
Just as I am free to roleplay that any Void Elf who claims they are in fact a high elf has gone loco from the voices, were I to roleplay.
Fact is the remaining differences are so small and minute that those holding out for a dedicated high elf race aren’t getting one. Blizzard sees threads like this and do they think about adding a distinct race? Nope, they just throw more options for roleplayers onto Void Elves.