It was probably closed because no one used it. I don't think there is much demand for an IRC anymore??
irc is long gone and not needed.
Sure, nobody's asking for it, but I reckon people would use it if it existed. Would be much easier and quicker for users to get help/discuss stuff without spamming.
I think sections have tried to have their own network/channel but it usually ends up being dead. If there was one big network for the whole forum, it would have users.
Think a periodic open IRC channel for discussion with staff/MentaL would be decent, a bit of contact and outreach with the community, once a month/once every quarter