An AI-infused search for hard to find discussions between team members that happened somewhere in the past is nice, I guess.
What I find slack enables though, is technical documentation being stored in such chats instead of something more formal, like an API or an up to date README.
Even more horrible is technical know-how being shared in video calls, as video-calls are easy to make, are interactive, you can draw, you can have fun, "it is easier and takes less time this way".