I have disagree with your interpretation. To teach implies the lesson has already been discovered and is just being passed on.

If you lived alone in a cave and independently discovered programming while there, I am not sure you are teaching yourself any more than scientists doing groundbreaking research are teaching themselves. We typically file that under research. It only said to be taught after the discovery.

The dictionary defines self-taught as learning without being formally taught. As far as modern lexicon goes, I have to side with the dictionary.