I love emails. For all mentioned in the post an one more: to write an email, people have to think before writing and email, even if it is just a few paragraphs. I takes focus, it takes asking oneself questions, what makes (in my experience) the quality of conversation way higher than talking with the same people over chat interface. Moreover, there is time for focus on email (both reading and writing) and time to actually work. (Vs chats that put some pressure on being always available which is something that literally makes deep focus impossible.)

Of course, some people treat emails like there were chats, and some people treat chats as if they were emails - yet, what's crucial is what's the reference level.

And yeah, in my experience and opinion, chats make us dumper. Just the same way as clickbaits and memes catch attention easier than in-depth analyzis, they are unlikely to go.