100% We quickly learn how vulnerable we are without a local language or Lingua Franca. In my experience working class immigrants who have immigrated to places

100% We quickly learn how vulnerable we are without a local language or Lingua Franca. In my experience working class immigrants who have immigrated to places that have no large established language community in their new home are the best demonstration of this. They often start with nothing but end up with great skills whereas others will just stay and interact with their native language community and be barely conversational in the majority language.