We've just become lazy in our writing. Despite the huge increase in short bursts of written communication, we don't tend to spend much time on even slightly longer bits of written communication.
yes, this exactly. lazy writers have shifted the burden of comprehension onto readers - instead of putting in the effort to clearly express what they are thinking/saying/feeling, they use a handful of inscrutable icons with ill-defined meanings...leaving it up to the reader to a) try to identify what that bizarre little picture is supposed to be, b) what it means in general, and c) what it means in the current context.
what, for example, does a sad face next to a duck mean? does it mean "i don't like ducks", "my duck just died", "a duck just shat on my head", "haha! duck-lips photos suck!" or something else entirely? it does not clearly express anything, just (possibly) something sad (possibly) involving a duck or perhaps another bird but duck was the closest picture i could remember or find quickly or perhaps something whimsically represented by a duck-like picture.
where no actual meaning has been conveyed, there is no actual communication.
if you want to communicate, it's up to you to do so clearly...not just scribble some inscrutable gibberish and expect your reader to figure it out. this is true no matter how simple or complex the thing you are trying to communicate.
words, by way of contrast, are a) easy to distinguish from other words, and b) have fixed meanings and don't require a great deal of interpretation (that doesn't mean ONE meaning per word, as words can have nuanced meanings, but a small number of meanings. the correct or most appropriate meaning can *easily* be deduced from the context)
communication involving hieroglyphs, ideographs, icons etc sucks because it is extremely difficult to understand what is meant (thus defeating its own purpose) and requires an enormous memory for the meanings of slightly different-looking pictures.
there's a reason why literacy is so much more difficult and uncommon in China - you aren't literate until you've memorised thousands upon thousands of different symbols and combinations of them. compare this to having to memorise roughly 20-50 different symbols (depending on the language - e.g most variants of the roman alphabet have 20-30 characters, while devanagari has 47) for the sounds/letters of the words. in both cases, you still have to know the words you're trying to write but in the latter you can write *ANY* words with just 20-50 symbols while in the former you can only write the words you have previously memorised.
in part, this has been deliberate - an illiterate peasant class is an uneducated peasant class and easier to control. the poor do not have the luxury of time or the money required to learn a skill that is nearly useless for their daily lives
democracy depends upon a literate and educated population, which is one of the reasons why the dumbing down of the population should be resisted in whatever form it takes (and that includes emoji and the over-dependence on short "messages" as a substitute for long-form writing)