In my opinion it should be updated with the times. I find myself writing multiple lines quite often, especially if I'm answering a question. Note that this doesn't prevent anyone from sending single line messages like usual, without markdown.

Forums are a totally different medium and I'm not interested in them at all these days. In the Korean discord I'm in, I can ask a question and get a response very promptly because it's just a chat. Sometimes this leads to questions being repeated, but I'll take that over a traditional forum any day.

Slack gifs ARE annoying, I don't see how they're not. Discord emoji is fine. Anyway, my point was that the comment I replied to constructed a strawman. When IRC people criticize slack or discord (or call them "frivolous"), it's not because of quality of life improvements like chat history, ease of use, etc.