The long-lost pre-drow like, aren't drow?
It's only the drow who followed Lloth underground and were cursed who got the dark skin, white hair, centuries of suffering to create their unique culture?
If lost civilisation pre-drow were around, they'd just be normal elves who live in jungles, have black hair, dark brown skin and memories of a fallen empire? I feel they'd be an elf sub-ancestry not a drow one?