Because they didn’t reinvent xmpp, they reinvented Google Wave.

A lot of Matrix.org is inspired by what Wave could have been - although we are running late with threading (but some work is happening currently there). From our perspective, one of the biggest gaps was the lack of bridging in Wave to other existing comms interfaces (eg email) - as well as the quirky UX.

Arathorn on Feb 18, 2018 on HackerNews