Just finished The World Until Yesterday by Jared Diamond this weekend and here is an excerpt I would really want to recommend, where you could literally replace “languages” with other words.
How do languages go extinct? … so too are there different ways of eradicating a language.
The most direct way is to kill almost all of its speakers…
The next most direct way to eradicate a language is not to kill its speakers, but instead to forbid them to use their language, and to punish them if they are caught doing so… the French government’s official policy is in effect to exclude the Breton language form primary and secondary schools…
But in most cases language loss proceeds by the more insidious process now under way at Rotokas… Young people in search of economics opportunity abandon their native-speaking villages and move the urban centers, where speakers of their own tribal language are greatly outnumbered by people from other tribal backgrounds, and where people needing to communicate with each other have no option except to speak the majority language…
Eventually, minority languages are spoken only by older people, until the last of them dies. Long before that end is reached, the minority language has degenerated through loss of its grammatical complexities, loss of forgotten native words, and incorporation of foreign vocabulary and grammatical features.