I've never once been on it yet I notice the game suffering constantly for having it. I warn all players away from it, and I think no one is better for having it in terms of the quality of the game.
It's so obvious to tell when someone is spending time chatting away on OOC about whatever rather than roleplaying their character IC. We already have issues with getting people to do stuff, providing an outlet to let players spend time in game not doing IC things is counter-productive.
It's the well-spring of toxic bleed in practically all the drama that has spilled out OOC from the game in recent years.
It's horrible for Sindome's PR and image. Almost every negative outside review of the game is critical of the OOC community and OOC-Chat in particular.
It splits discussion between forums and live chat which has no record.
The majority of staff feedback seems to exist in OOC-Chat compared to the forums, lost to ephemera unless someone happens to post it to a relevant forum topic.
It forms extremely obvious player cliques that bleed into IC gameplay.
It often degrades IC SIC into memery and shitposting.
I know some staff like to chatter casually with players but I think in a game like Sindome which cracks down on every possible form of OOC communication or bleed, having this channel is utterly counterproductive.