Morning wood emoji when?
https://biblioklept.files.wordpress.com/2013/05/twain_ma881-...
While painting/photos can express multiple, deep emotions, they are unique. The value added by a copy it's none.
Moreover emojis are for 99%+ simple nouns ("hand", "pig", "dog", "smile"). And for thing that are not nouns, you still need to understand that they are logograms, with a "fixed" meaning. Kanjis are not better than Romans - they are just different alphabets.
And if you think about it long enough you will find that there is already a 1-to-1 mapping behind the "emojis" and the words (by definition, the unicode is the mapping of numbers - the code point, to meanings - the name, and to images - the pictogram, so you can have U+1F436 associated to 'DOG FACE' and ) , so they are "informationally dense equals" between each others.
But well, you don't need ice cream cones and airplanes to compensate for loss of body language, unless you routinely pantomime those things.
Instead of selecting an easily compressible format for embedding any small image inline with text, we're trying to force a writing system into a kind of general-purpose icon library.
We could've had a world where carriers and phone manufacturers each had their own "common" images easily entered from some list like now, but still allowing cross-platform transmission without information loss, and enabling users to easily add their own custom images.
Now Unicode is stuck trying to define a finite set of popular words which every platform renders slightly differently, and will always leave something out or offend someone.