ok hear me out reacting to discord messages with emojis essentially serves the same purpose as aizuchi (interjections that show the listener is paying attention or understands the speaker). if a friend is going on a spiel in discord DMs, reacting with emojis to successive messages can be a more efficient way of showing you're listening without interrupting the flow of messages by responding with "yeah" or "yep."
and then you have custom emojis that vary across servers which allow individual servers to develop their own emoji dialect. joining a new server and looking at its custom emojis scratches my linguist brain because immediately i think about when/where/how said custom emojis are used.
i also think about nitro discord users being able to spread server emoji dialects (but only to a limited extent because regular discord users can't save and use custom emojis outside of their original server). i've now been in a handful of interactions where i've had to ask about the etymology of certain custom emojis and the explanations i've received are always fascinating.
