Slacks problem isn’t with generating things to say, it’s with managing attention spans and navigating between conversations easily. If the integration can help with that, maybe it will make sense. But if it just helps people write, that is nice but I’d be concerned that it would lead to longer and less direct messaging.

Edit: Read further in. Maybe it will cut down on the number of messages people need to send for things that exist in slack but that no one bothers to read. In that way, it could be pretty useful. I’m assuming Microsoft Teams has something similar already?