Oh, I agree. It has more to do, for me, with how it feels in my work. A typo - at least one that doesn't auto correct - messes up the flow.
It's probably a personality thing. I remember many years ago with early computers, my brother would talk about how it was no big deal to have to wait a few seconds for the computer to move from one thing displayed on screen to another. But it drove me crazy. I even recall the first program that I felt finally got it right (Time Is Money). It was a financial program and when you hit a key to go to another screen, it was instantly right there. Other programs always had this little delay. I loved it because I never felt like my train of thought was being interrupted by waiting or, in the case of accurate typing, by having an error.
My annoyance with errors may also have to do with being a musician. One wrong note out of 33 is NOT good! Heck, one out of 100 is not good!