Have you read the article? The condition has to be stronger than simply not teaching it to your children. You have to absolutely and completely remove the worldview, cultural heritage, geographic knowledge etc that comes with it.

Thus to get my (and the article's) point, you need not just stop teaching it to children, you have to completely erase the underlying knowledge the language holds and start over in a new language. This is the point: you lose much more than what appears on first glance.

And concerning programming languages, I don't see how picking up brainfuck for example is easy, but someone still put the effort into creating it. Imagine a universe in which you'd have to solve every single programming problem in C. You could dream up all sorts of programming language concepts, but you could never use any other language than C. I bet you'd find that a bit boring and tedious...

Make no mistake, I'm not advocating for languages to keep their purity. I think it's a good thing they mix and borrow concepts and words. But I do find the idea of having one world language an utter absurdity.