So if it wasn't written in the average sentence structure, why is that poor reading comp and not poor writing comp? Couldn't you argue either one, depending on who you want to criticize?

How can you say you're good at making sure you're understood and yet also say people struggle with reading comp? Are you saying that people don't struggle with your words, but you watch them struggle with things others wrote that you understand? Are you sure about that? Or are you drawing self-serving conclusions here?

Ultimately that's all this discussion can be. If you assert that there's some sort of standard of "reading comprehension" and that some people lack this intelligence, you're already starting a conversation that puts you above them. You float right on by the central struggle of human conversation - being understood - and just pick your favorite winners and losers.