But the screen reader needs to say the word, and the pronounciation of "coin" isn't the same in every language. I don't know about Irish, but it's radically different between French and English, the only sound in common is the "k".

This means that if the screenreader picks the wrong language, then the user has to guess the spelling from the way it's pronounced to understand the text.

Though I'll concede that right now on the web it isn't much better; but that's a failing of publishing tools, not the format.