IMO, it depends what kind of communication you’re trying to initiate. Chat can be used for both “one-shot” asynchronous queries or notifications (the example in

IMO, it depends what kind of communication you’re trying to initiate. Chat can be used for both “one-shot” asynchronous queries or notifications (the example in the link) and for synchronous, interactive discussions—chats! If we could reach cultural consensus, it’d be great if a bare “Hello” / “Hi” / “Hey” let me know you’re attempting to initiate the latter.