This is a broad question. However, I think there's more to it than meets the eye. Yes, I do speak multiple languages fluently due to my studies, but I never thought much about it until now.
In America, it seems academic jobs are very competitive and only the very best PhD students from the top universities can gain a "tenure track" position. For instance, in my field of philosophy, it seems that only the best students went anywhere. It is very competitive to get a postdoctoral fellowship and even harder to get a tenure track position.
Recently, however, I noticed that you don't need to necessarily be a part of the philosophy department to teach philosophy. I knew, for instance, a postdoctoral fellow in the Spanish department who studied philosophy yet he was given a post-doctoral fellowship as a Spanish instructor and I think he continued to become an assistant professor. He studied philosophy in Spanish and gained a PhD in the field. Yet he was still able to teach philosophy in Spanish and publish his books about philosophy in Spanish. Since he taught the 301+ courses most of his students had no issue with the philosophical content of the lessons.
My observation is that sometimes different departments won't talk to others. Like the philosophy department won't talk to the Spanish department. In the Spanish-speaking world, people were familiar with his work and read him. Hence, he did not need to be part of the philosophy department to write and teach philosophy at university.
What do you think?