As Blood Elves are High Elves, of course they won't go extinct. As Void Elves are a variant of the high elves, that also means they won't go extinct.
But the topic isn't that the exiles are extinct, it is that the exiles are 'nearly dead'. Which is in fact entirely accurate. They ARE nearly dead. There ARE only a handful of them left. They ARE scattered across the world. And they ARE assimilating into their host societies. That is the canonical status they have. It is the lore rationale for why they were never made playable.
Getting pissed off because someone makes a reference to that canonical, unarguable status that they are nearly dead and then insisting they aren't is simply being ludicrous. It's like getting angry because someone stated the Horde capital is Orgrimmar.