I presented evidence in the form of the Ask CDEV quote and the principle of how the Sunwell acted in the past. That you ignored it is unsurprising. By your own words you have admitted anything you can't reconcile to your view on this topic, even if it comes from the developers, is ignored. Conversely, anything that you agree with, no matter how questionable the source, is exalted.
But the principle stands. Blood Elves and the exiles remain the same race, bound to the same Sunwell and sharing the same destiny, which is really the principle at stake here as nobody expects any universal eye colour shifts within the lifetime of World of Warcraft. Ultimately, the blue eyes are just an eye colour, a circumstance of the moment, held by those elves who were outside Quel'thalas. Just as the golden eyes are just an eye colour, and the green eyes are just an eye colour.
A high elf is as different from a blood elf with green eyes as a blood elf with golden eyes is different from a blood elf with green eyes or a high elf with blue eyes. Thalassian elf eyes just work that way.