Sadly, we don't even invent new protocols any more, at least not open ones. What we do is invent new, closed platforms like Slack (and HipChat and Campfire before it).
I use jabber with a friend, and frequently messages go to his other laptop, which he doesn't see until he logs onto it. Same in reverse. Similarly, history isn't unified. You can get around these problems by having your own centralised jabber chat client (like bitlbee), but that's a technician's answer, not an answer for the general public.