The languages that are vulnerable are vulnerable https://en.wikipedia.org/wiki/Endangered_language

Vulnerable to going extinct.

If you read the article it briefly touches on how the “doom spiral” could affect the trajectory of a language that is not widely spoken. It’s not a great article though, it just repeats the same thing for several pages, points the finger at wikipedia instead of the content-generation farms and then fails to properly conclude the argument of their presumed hypothesis.