I would agree that emoji have basically failed. They confuse communication rather than facilitate it.
Why are there ๐ and ๐ ? "Grinning face" and "Grinning face with big eyes." Why? There are so many of them with subtle details like this that A. choosing between them is a bigger chore than it should be and B. they have to be rendered at such a high DPI that "bro just increase your font size" becomes the bullshit workaround everyone tells you to do. I can read the English text just fine, but on most screens emoji are indistinct blobs.
Emoji are subject to all the variation that fonts are. You know how there are two lowercase "g" glyphs? There's the one you probably do when handwriting which is an O and a J, and then there's the loop over a loop that basically no one hand writes, it looks like the font Lemmy uses has that g. Well, emoji are like that. Like how they had to add "male dancer/female dancer" the the standard because Google rendered the "dancer" emoji as a lame disco man, Apple rendered it as a woman in a red dress.
They don't get used the way we used to use emoticons. I don't see people say things like "I can't go to the park today โน๏ธ " I see people say "Hey guys ๐ฌ I just got back from the store ๐ช with some groceries ๐ฅซ and took a picture ๐ธ of my dog ๐ " Which to me demonstrates a failure to grow past the Sesame Street book with 6 thick rigid pages reading level.
Finally, there are so many symbols that have alternate meanings that you just have to know. Like you can send white or tan or brown faces, but all eggplants are purple and all peaches are pink.