I don't agree that it's not worth it to learn a language if you're not going to use it in that language's culture. There have been studies that show how the process of learning new languages actually causes positive changes in your brain that can have a lot of benefits, even if you don't remember the language forever. For one thing, once you have those connections in your brain, it allows you to learn languages more easily in the future. It also helps you with things like critical thinking and abstract problem solving. Definitely not a waste of time.
I don't agree that it's not worth it to learn a language if you're not going to use it in that language's culture. There have been studies that show how the process of learning new languages actually causes positive changes in your brain that can have a lot of benefits, even if you don't remember the language forever. For one thing, once you have those connections in your brain, it allows you to learn languages more easily in the future. It also helps you with things like critical thinking and abstract problem solving. Definitely not a waste of time.