I didn't want it but now that it's here and many people did message me (usually asking for something) I would feel upset that all that history is lost.
Thank god I made a data request last month asking for everything in my account. I have all my 10+ years of Reddit history backed up elsewhere.
I did use it a few times, but only as a 1-to-1 message. The inbox was more efficient anyway.
I think they had subreddit general chat but I’ve never used that.
I’ve seen it used for live events (think press releases or keynotes), which I think is probably the best use case for it. As a general chat platform it’s pretty useless.
If chat is what I'm thinking of (the private DM feature), then I used it once or twice. Namely, when I wanted to send a link/file to users in a community where posting links or files were not allowed, or being on the receiving end of that, wanting to privately message someone asking for something.
Tbh, it's not a system that needs to be overhauled and enhanced. It should just do the bare minimum of letting people privately message each other in a more streamlined format (a chat, as opposed to the equivalent of sending e-mails back and forth)