As someone who's been on irc since the mid 90s and have had and still do have a couple of Irssis running in screens for 10+ years, I have to say that irccloud is pretty great for ease of use. There was an open source clone called ircanywhere, but it seems abandoned.
I have no idea what the future holds, and I always welcome new tools and disruptions, and I'm using slack, discord, messenger etc for various communities. What keeps me from leaving irc is:
* friction in moving all users that have been using an IRC channel for 20 years
* stupid stuff in slack and messenger like lock in and slow search. I really like grep:ing logs for links and discussions and then reading the context up and down, which I have found difficult in web services.