I went through school, having classes for Spanish for 4 years and Italian for two. It was obligatory to choose a third language. The second I was done with school, I had already forgotten everything I learnt of those languages. If I am not gonna use those languages daily I will forget them. It was a monumental waste of the students time. Now I have a spouse that speaks another language, that was never an option to learn in school. We both speak english though. There is little way to predict what languages will be useful for a student. English as a second language is a good bet. Every other european, except Russians, have been able to communicate with me in English. 99% will never benefit from a third language. They should have taught computer science or something instead. Before LLMs I thought they should at least have focused on teaching languages that were hard to machine translate. Like Russian, Japanese or Korean. That is my opinion.