Weren't facebook messenger and google talk based on xmpp?
I know that at least they were compatible, but in the end they removed that. Trying to force people on their own client
This is the problem - if you have a large user base there is simply no business incentive for federation. It is so much easier (and cheaper) to just build your own silo without worrying about interoperability. Plus you have the ability to monetize a closed system through ads, data mining, etc. There are so many advantages.
And people don't complain (much) because, for chat especially, they have had years of conditioning that leads them to accept (and expect) that communication with their online contacts depends on installing multiple apps from multiple vendors and sharing their data with those vendors on whatever terms the vendors decide.
And people don't complain (much) because, for chat especially, they have had years of conditioning that leads them to accept (and expect) that communication with their online contacts depends on installing multiple apps from multiple vendors and sharing their data with those vendors on whatever terms the vendors decide.