If I’m reading this correctly, the vast majority of born-deaf people don’t learn how to fucking read?

Yep.

In addition to what the other person mentioned, there's also some real difficulty in establishing a language initially. I can't teach you to read unless there's another language to scaffold that off of. If you don't understand spoken english or a sign language, and your parents and teachers don't understand a sign language, and their spoken english isn't getting through, how are you going to learn much of anything?