This isn't really an accurate comparison:
High Elves literally are Blood elves. They are the same exact race separated by a cultural schism that happened less than 2 decades ago, a schism that no longer even seems relevant since the Sunwell is back and the Blood Elves have rejected any kind of fel influence or siphoning power from unwilling hosts.
Nightborne have been isolated for 10,000 years and developed into an entirely distinct people both culturally and physiologically.