>I'm very disappointed to see that Slack has decided to go the way of every other messaging service and move away from decentralized and standardized protocols
If every major messaging service eventually does this maybe those decentralized and standardized protocols are the problem.
I don't have any data to back this up, however, I suspect that standard protocols leaving little room for vendor lock in is the primary driver behind the closed systems we're seeing today rather than some inherent limitations open protocols.
(I'm not saying the current open protocols are perfect, or even close, however - 100s of closed chat protocols have been built and rebuilt - that effort would have been better spent in the open IMO. Obviously, investors and similar business functions see things differently though.)
We already know XMPP has issues, but these aren't enough to cause its continual addition to chat apps and then removal. More than likely, the "problem" with these protocols is that they don't help a company's bottom line, engagement, etc.
If every major messaging service eventually does this maybe those decentralized and standardized protocols are the problem.