What about reusing and polishing XMPP and existing decent software for it? About donating money to people who develop it all these years? No, we'll spread FUD upon XMPP or just ignore it but will proceed to use and abuse its legacy behind the closed doors.
It may look intimidating at first, but it's really very easy once you get the basics.
HTTP and IRC on the other hand look easy at first, then you get past that and there's just more and more complications and edge cases and horror. Like all the various cache headers and behaviors in HTTP, or how all IRC networks have their own dialect that's subtly different.
I once tried to work on an IRC server interface, I read all the RFCs, wrote code, then tested with a client. Nothing worked, so I had to resort to replay what the client sent to a different network and reproduce whatever they did.
If you go read the XMPP RFCs, you should be able to write a client or a server that gets along pretty well with the rest of the XMPP world.
This may be the primary reason for the multitude of protocols. Everyone thinks every existing protocol is complicated and thinks that they can implement it better. Or: https://xkcd.com/927/
http://risovach.ru/upload/2016/03/mem/novyy--shablon_1085837...