I think the main benefit (apart from practical reasons) to learn a language is the associated translation of culture that suddenly is not removed by a degree of

I think the main benefit (apart from practical reasons) to learn a language is the associated translation of culture that suddenly is not removed by a degree of separation as before. You can think of it as lossless vs. lossy information transmission. If there is any translation step, then the transmission is lossy. Sometimes terribly lossy. With Esperanto... well, it's invented isn't it so at this point there is no cultural benefit. But then again, Klingon afficionados are probably culturally pretty colourful.