The thing is people have suggested Zero in Reboot multiple times on the forums. There never were that many replies, but the thing is at this point people feel suggesting it again will accomplish nothing.
It accomplishes nothing because Nexon never even acknowledges the suggestion. The previous CM looked into it but never provided a follow-up, and Arwoo only mentioned "we'll look into it" which is just polite talk for "bugger off, stop bothering us, it's never going to happen".