If I were completely nonverbal, at least people would believe me when I tell them that sometimes I am literally incapable of speaking, instead of insisting that I just don't want to talk. No one at all who's met me in person believes that
And it would take away all the stress, energy drain, and frustration of trying to speak - it takes much less effort for me to communicate in writing, and I wouldn't have to repeat myself over and over, each time becoming even more difficult than the last because being asked to repeat myself increases my stress, making it more difficult to talk. I have a text-to-speech app on my phone - I'd much rather use that instead of speaking, but my parents get angry with me if I even suggest possibly using it. I really wish I had something I could use as an excuse so I could switch to entirely nonverbal communication without being constantly scolded for it. It would be much easier for both me and everyone trying to communicate with me.
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"