So, Blood Elves kind of are High Elves with different eye colors and backstory in terms of their relationship to magic in the Sunwell. But if you want to be a fair-skinned, light, blonde-haired, tall, majestic, elf...that is a Blood Elf.
Giving that race directly to the Alliance would have blurred a lot of the lines between the two factions, but also there isn't a clear example of who or what High Elves are as a larger group which remains in Azeroth. There's a couple...we just met Alleria again...but they're not out there in the same way. When we add an Allied Race, there's a desire to have things be even more distinct especially between the two factions with the faction conflict being so prominent. And so, the Void Elf angle, as it tied into the story of Argus, the powers of Alleria awakened and was able to train others to harness, was able to give something that felt a bit like a Blood Elf but had a unique flavor of its own to the Alliance.
That said, obviously I understand you would love Alliance elves...you're an Alliance player, and want to be a fair-skinned, light-haired, blue-eyed elf. Sorry? The Horde is there and waiting for you. Eye color is not quite the same but maybe contact lenses in the future, you never know? Anything is possible in the future, but no plans in the near-term to add High Elves as an Allied Race.