There’s no escaping the fact that the way we speak has been shaped by the way we write. You could say that in a literate culture, speech tends to follow script, which is the opposite of what is called phonemic orthography, the writing of words based on the spoken sounds (graphemes matching phonemes). It seems that as languages evolve from a purely oral to a mixed (i.e. oral-literate) environment, speech adopts the qualities and properties of writing. It becomes less diverse and more stable.
Human verbal communication is still predominantly oral. We use writing more than at any point in our history, but most of our language-based interaction is done with speech. Yet, the presence of writing in our spoken language is remarkable. We dot the i’s and cross the t’s, highlight a point and underline an argument, and we learn to mind our p’s and q’s. Most literate languages seek to mimic the written environment, the express the visuals of script through the spoken word.
Onomatopoeia is the triumph of audio over video, of spoken language over the written word. The rapid and widespread progress of literacy in modern societies have pushed sounds to the edges of respectable communication: you’d better speak as you write, and not the other way around. But the advent of the digital age is bringing the sound back centre stage, restoring the diversity and messiness of human language.