https://wowwiki.fandom.com/wiki/High_elf_NPCs
105 Named NPCs.
That link I posted also summarises where unnamed High Elves can also be found, and in what numbers. There’s about 100 of those as well.
https://wow.gamepedia.com/Category:High_elf_characters also supports this, listing 246 different named or generic NPC types.
For comparison sake, I’ll list the other Allied Races (Except for Kul Tirans since I can’t find a page for them)
Zandalari amount to 671 named and unnamed types of NPCs. However, a lot of these are mobs fro mprevious content and are likely dead or redundant now. But still, we’ll use that number for the sake of the argument: https://wow.gamepedia.com/Category:Zandalari_troll_characters
Nightborne amount to 411 (with a large amount of the named NPCs now dead, as well as the Felborn/Felsworn etc): https://wow.gamepedia.com/Category:Nightborne_characters
Dark Iron Dwarves sit at estimated 281 (most of which are nameless NPCs for quests/dungeons/raids): https://wow.gamepedia.com/Category:Dark_Iron_dwarf_characters
Mag’har Orcs? Surprisingly, only 127: https://wow.gamepedia.com/Category:Mag%27har_orc_characters
Meanwhile a combined list of named and generic NPCs of Highmountain Tauren lists only 120: https://wow.gamepedia.com/Category:Highmountain_tauren_characters
Lightforged Draenei sit at only 68: https://wow.gamepedia.com/Category:Lightforged_draenei_characters
Void Elves sit at 32: https://wow.gamepedia.com/Category:Void_elf_characters
So basically the tl;dr here is that if High Elves aren’t numerous enough to be a race, then over half of the current Allied Races, based on in-game representation, shouldn’t be either.