Weren't humans domesticated by the requirements of the plants and animals themselves? - H. Russell Bernard

It is not necessary to argue that language diversity caused the evolutionary success of humans. We need only recognize that the knowledge generated by all those successfully adapting cultural groups over the millennia is stored in all those thousands of languages now spoken around the world.

I see nothing useful or charming about remaining monolingual .. if that results in being shut out of the national economy.

As a university professor I sell what I know.