Blizzard isn’t going to deny a spec(s) to certain races.
True.
I always thought the Forsaken’s eyes were more Jaundice than holy light yellow.
Oh well… 
Nope. Priests channel the light, but that doesn’t make them holy.
That whole “Priests only channel the Light” thing is proven to be Out-of-Control-Headcanon by in-game Priest Abilities.
Like Power Infusion where they infuse themselves with the Light or Apotheosis where they transform themselves into pure Light.
So says you.
So say the Game.
“Enter a pure Holy form for 30 sec”
Transforming into a pure Holy form goes waaaaaaaaaaaay beyond just channeling the Light.
Wow for a whopping 30 seconds. Being able to withstand the pain of the light for 30 seconds is a far cry from being holy. It’s ok to want to be a real priest.
Yes know you’re right. You should have other colored eyes.
There was a lot of nonsense about Derek’s white glow in his eyes meaning that he was a Lighforged undead. When really it just looks like Blizzard was going for the milky film that forms over your eyes when you die.
It’s just a limitation of what they can show.
That’s twice the time a Vengeance Demon Hunter’s metamorphosis lasts.
Are you telling me that Demon Hunters don’t infuse themselves with Fel?
I said you were right. Be gracious!
NEVER! 
Yeah look how holy you are. Fraud. Pus filled fraud.
Maybe Forsaken actually have poorly designed Jack-O-Lanterns for heads?
Give us Humans Glowly Yellow Eyes of the Holy Light.
Let the Turalyons or Natsus of Fairy tail became a Reality in WoW.
It’s spectral not holy.
But Turalyon is in WoW…
No one heard from him in years until last expansion, according to the loading screen tips.