Eh, I personally wouldn't be so hard on someone because of language. Words don't have definite meanings on their own, it's our general agreement that makes them meaningful. And the meaning of words are often overlapping, shades-of-grey kind of deal, with even more subtle differences in individual understanding of them. Language is hard.

Moreover, polite explanations may bring enlightenment, but aggressive scoldings are almost guaranteed stop people from accepting your words, even if they're true, because in order to accept their truth, they have to accept the unpleasant implications of your words.

I think learning should generally be as pleasant as possible. Putting the work in is hard enough as it is.