Why not? Do you also don't want to see icons in GUIs?
Why not? Do you also don't want to see icons in GUIs?
But the main reason not to use emojis would be that you have no idea how they'll look to the user. I tried to paste the example output from yubikey-agent into my terminal, and all I got was a bunch of differently sized squares. Very informative...
Symbols are universally used for quickly warning/informing in the real world and if done well, are very intuitive. Ignoring them in the digital world would be going against human UX (but no one ignores them, of course, even very old CLis already used them, but with the widespread use of UTF-8 and Emojis with that, it just became much easier and better).
You can easily output tables, bullet lists and many other things just with basic symbols supported everywhere. If your CLI program requires installing fontawesome or breaks in a terminal multiplexer etc. I'm probably not going to use it.
Visit https://emojipedia.org and notice how all emojis have their own code point :)
Many people use the terminal exactly because it displays fewer kinds of content than e.g. a web browser, which as a side effect simplifies many situations.