I was actually just adding more criticism. They obviously negated that people can have more than one native language. There is a lot to criticize on that presentation. I'd file it under "Data can be ugly" tbh.

On the other hand, doing this "cleanly" is imo nearly impossible. The language situation is way to complicated to present "the demographic of languages of the world" in a single graph without oversimplifying and misrepresenting stuff.