To quote Kael’thas…
“We must put this misery behind us. We must enter a new chapter! And so I say to you that, as of this day, we are no longer high elves! In honor of the blood that was shed throughout this kingdom, in honor of the sacrifices of our brothers and sisters, our parents, and our children, in honor of Anasterian… as of this day we will take the name of our royal lineage! As of this day, we are sin’dorei! For Quel’Thalas
— Kael’thas Sunstrider
Let me repost that for you…
We must enter a new chapter! And so I say to you that, as of this day, we are no longer high elves!
Once more for the people in the back!
we are no longer high elves!
Do you understand yet?
It’s the same concept as to why Australians and Americas are no longer British.