But I think it is more complicated, because it also makes clear that IRC is not an ideal medium for many forms of messaging. It works great for free for all chat, where the discussion happens right now. But it is not great for group chats with friends or when information needs to be disseminated across a community, but I have both of these seen used often.
It just not asynchronous, while at the same time, because of the constant open connection, also not great to use on the go.
It's somehow nice to have a medium for "right here and now", but it sucks to not be able to answer a question or miss important conversation because you didn't look for 10 minutes.
Of course, multi-tier conversation options have helped traditionally, but I think that's also why i never bothered with IRC much, because it was always 3 dozen people idling who always seemed to burst in conversation once you got disconnected.