Why don't they make chat official? Is there a negative of everyone having chat?
Chat becoming available to everyone is bad for several reasons:
1. It will open floodgates of spamtrolls clogging up servers.
2. It will encourage half the server to stop playing and start chatting (especially newbies just starting the game and seeing people talking, wanting to get in on the social part of the game).
3. It will no doubt create lots of flamewars as newbies argue the skill of experienced players, claiming they're cheating in some way. Or simply trolls looking to be trolls, instigating flamewars. With chat pretty much exclusive to forumers, there's not much flamewar going on. We all generally know and respect eachother.
4. Newbies will start relying on chat instead of emote bubbles to communicate in game, which will only make them even MORE useless because they'll now be standing still and not doing anything. For instance, they'll stop playing to yell out SPY! instead of going

, allowing that spy to get a stab.
5. It'll allow a whole lot of aggrivating newbies to start yelling out racial and sexual slurs at little to no provocation. This will not only ruin the fun for experienced players that don't enjoy/aren't used to hearing people bicker like 12 year olds when they're trying to play, but will also instigate flamewars and long non-playing moments as newbies call eachother slurs back and forth like some kind of playground debate.
6. And above all else, all of this combined will probably force the experienced forumers among us to simply stop using chat, or even stop using GG2 altogether because half the server won't be playing, will be arguing amongst themselves, will be even less of a challenge than before, and will be even less fun than before.
As for the topic itself, I think someone someday will create a mod with chat functions, kicking/banning etc, similar to Vindis. After all, nessessity will require modders to get on the ball and use Vindi's source stuff to cobble together something updated with current GG2! Some sort of knockoff Vindi's mod will probably pop up someday.