There are other groups who heavily use these features. We've got over a thousand custom emojis in my Slack at work. Our interactions would be just slightly less rich without :badpokerface:, :sadpanda:, or :superhero:.
For some reason these IRC vs X discussions always have the IRC party attributing character flaws to everyone else.
Like not being creative enough to read the same amount of information from ":)" and specific, rich, custom emoji like, I don't know, someone simply shrugging. That's some bizarre self-aggrandizement.
I encourage you to go on a Twitch channel and tell me the :) equivalent of all the custom Twitch/channel images you see in chat.
And that's fine. None of us want to take IRC away from you. And it's fine as well for you to advocate for IRC, so new people can find out about it and join it. Some of us like other chat services though, for various reasons, and we enjoy using emoji in playful ways and to supplement the lack of body language in written communication.