While I don't know, I have a guess: Google loves building infrastructure, and they're pretty good at it. XMPP wasn't build in-house, and writing a replacement p

While I don't know, I have a guess: Google loves building infrastructure, and they're pretty good at it. XMPP wasn't build in-house, and writing a replacement protocol was something Google could do. What Google absolutely suck at is UI and native applications (at least on the desktop). It's also why their products keep failing. Seriously how hard would it be to build native clients or open the protocol and have it integrated into libpurple. I find it extremely hard to comprehend why Google don't just hire five of the worlds best macOS developer, five Windows developers and five for Linux/BSD and just let them build fantastic clients that integrates into each platform and provide the very best chat experience.