> “The initial project was created inside Amdocs, while building a chat tool called "Amdocs Unified Communications”
This is true; I created it. With a team, including myself, who had been acquired into Amdocs and operated as an independent unit. As I already said.
> As an insider, what do you think was Amdocs’ reason for building a whole new chat protocol?
Our pitch to Amdocs was that RCS was not fit for purpose, and XMPP was building on top of outdated primitives which didn’t reflect the synced multi-device group-chat experience of comms app which were becoming standard at the time in 2014. To be clear: the idea of Matrix was our idea; Amdocs deserves significant credit for going along with it and funding it in the early days.
> Why would they pay big money for decentralization?
They didn’t pay big money - they funded a ~15 person team for a few years. They supported decentralisation because if you’re building something which could replace the phone network, it needs to be an open protocol which anyone can independently implement, run, and verify. Including conspiracy theorists on HN.
> Why wasn’t Slack or SIP+XMPP good enough?
Because Slack is an unencrypted proprietary centralised chat vendor, not a communication protocol.
SIP+XMPP was a horrifically flimsy approach, which duplicated functionality and risk of bugs, while limited by both protocols (eg lack of e2ee and group calling in SIP; lack of synced conversation history in XMPP at the time).