Originally they did, before TBC went live, they actually left the quest text in referencing it for one of them who says (Paraphrasing, my memory isn’t -that- good ) “Don’t let the eyes fool you, I’m a High Elf, not a Blood Elf, I won’t suck the life out of you” A Direct reference to the fact that she does look identical, right down to the eyes. Later in one of the CDev Q&A they confirmed exactly how Thalassian Elfeye glow works, and that is where they stated “If you were a -High- Elf and went to Outlands, you’d get Fel- green eyes”
Apparently the reason they didn’t implement it in live TBC was because it would cause ‘confusion’ to the player base, which to be honest is vaguely patronising, given that Allerian Stronghold’s guards don’t attack you if Alliance should be pretty obvious that it is an Alliance settlement!
Reason I mention the quest dialogue is that presumably the ‘Hero’ is a grown adult. They will likely have seen a High Elf before, so why would the High Elf Questgiver specifically make sure they know she is not a Blood Elf if it would have been readily apparent by her appearance?
But yeah, Blizz explained it more fully in the CDev (I’m pretty sure it was number 3.
That indeed makes no sense, it could have just been an error given that he does just use the Blood Elf model which I guess back then would have come with green as a default. Had not noticed that about Arator, interesting, but yeah, he should have had blue eyes initially, as he never lived in Silvermoon (Same as Lanesh the Steelweaver, a Blood Elf, has blue eyes because he lived in Dalaran during TBC, along with several spawning Sunreaver Mobs during the Purge), which maybe would have changed to Fel green later.
This said, he is a Half Elf, perhaps it was conflicting between his Human and Elven nature, that’s one thing they did not discuss in the CDev Q&A, whether eye glint effects Half-Elves as well… Ehh, who knows…
It is, including in alternate Timelines according to Blizz, I used the wrong term is all