And each iteration is basically worse.

XMPP should be able to be a Slack replacement.

Hangouts was a proprietary reimplementation, that had most of the features in an awkward way. Group chat in columns wasn't a great idea but was fine on mobile.

Duo/Chat was weird, separation of communication for no great benefit, and wasn't really any better than Hangouts. More like Hangouts that they had given to an intern to fix up, but forgot to tell them that it still needed to work with Hangouts.

Now we have Chat and Meet, Meet "replacing" Duo, while Duo is becoming Meet?

All I know is that after Hangouts finally was retired and replaced with Chat, they hid the chat tab in gmail, and required you to unhide it, and then appeared to disable notifications so I never knew when the last couple of people using it messaged me.

1/10. Wouldn't recommend.