Not so much as you might first think. As in I can type a page of gibberish Google transcribe is pretty good at ensuring that sometimes. I might have a personal flaw where for whatever reason proof reading doesn't always happen. What I find really disturbing is the amount of acceptance there is behind oh hey you made an error you must be retarded.
Sometimes it's worse than that. Message can be properly formatted to semantic rules. That doesn't mean the reader or listener has the required prerequisite knowledge to make any sense of it. Even in those cases I've found t's somewhat disturbingly common to see That's incoherent You're retarded. Or some iteration /variation of that.
It's hard to know what someone's motives are. Usually those who think they can with certainty are drunk on themselves to say the least. That said it's also hard to communicate with precision 100% of the time and somewhere in the compression algorithm it's often lost and absolutes take its place. Which at one time we knew don't jump to conclusions either. Judge a book by its cover etc.
What I'm trying to say is maybe some of the people saying this have reason to discredit some messages so perhaps it would be short-sighted to say it's always brain down in short personality disorder. That said nothing says the two can't coexist.
Live and let live as a philosophy one would hope would allow the two parties to but I sort of fear for how long that's going to work
Psychology as identified that it only takes something like 30% of a population either conditioned or on their own will having decided to believe something. It only takes for what?
To influence the behavior of nearly 100% of the population.