This is just a quick argument for why we should use IRC.
I have used Slack, Discord, Mattermost, Zulip, Telegram, Whatsapp, Messenger, Signal, Matrix and many others - and the one I keep coming back to is IRC. With such advanced tools, why do I keep going back to one of the oldest widespread communications protocols?
A potato could connect to IRC – The protocol is simple and it works. You can even connect via telnet or nc and manually write the commands to connect, it really is that simple. With half of the protocols mentioned previously you need some massive Electron (or JS framework) using up significant amounts of CPU to even have a hope of working. You should not require more CPU power than rovers on Mars just to talk to one another via text.
Reliability – It hardly ever goes down and it never needs servicing, the protocol is so well understood that some of the software has been mature now for many years. How many times has your team lost it’s vital communications for a few hours because somebody tripped over a wire in California?
No vendor lockin – You can switch to any server, run your own server, run any client, run no client - you are really free to run IRC how you want.
Messages are not saved offline – When you first login to IRC, that is when you become available to talk. I think that with current chat apps you encourage FOMO (fear of missing out) and this has a negative impact on how people behave. I really do not want people contacting me when it is convenient for them. (This is one of the reasons I hate phones.)
Writing bots is easy – You can do it in any language that has networking abilities - you do not need some crazy API or library in order to get a bot operational. The flexibility is simply unmatched.
Coffee Space 
