It's not a matter of technical, scientific correctness. It's just simple linguistics. Every language subdivides the world into different categories, and how they slice it up varies. In some languages the general term for bats and birds may the same, and would correspond to "flying animals" in English. Fish and whales? Same.Now we are getting some where. You claim they were wrong based on current knowledge yet ignore the fact that in their time is was correct calling something kind.
French divides "chairs" into chaises and fauteuils. In German "wall" can be a Mauer or a "Wand."
"Kind" is such a general term that trying to use it in any technical sense is absurd.