system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: I think everyone on earth should speak the same language.

I think this would create a greater unity among all humankind by making communication with different people much easier. 

I understand that, to an extent, culture is tied to language, but many people of other cultures still practice those cultures while speaking english. It doesn't seem like other cultures would disappear if all people spoke one language. 

In fact, the fact that language is a part of culture seems to provide even greater evidence that speaking one language would bring the world closer together, by making all cultures that much more able to understand/empathize with each other.

Edit: I am not arguing for one particular language over any other. Also, this is regardless of how everyone comes to speak the same language (maybe starting with everyone speaking it as a second language would work best?), I'm just arguing that if they did, it would have a positive effect overall.
gpt
One of the most underrated parts of any language are the words that are untranslatable to other languages. For example, the English word serendipity is notoriously hard to translate into other languages. In Spanish, the word duende is famously hard to translate. And there are countless examples from other languages of words that do not translate well or at all to other languages.

Why is this important? Well, these untranslatable words give their languages a special feeling that no other language has. Their existence and usage can tell you about what the people of the other culture might value that you might not.

Not only that, but the grammar between languages is so different, that sometimes whole works of literature are difficult to translate. Take The Metamorphosis for example. It's first sentence is famously hard to translate into English because English grammar and German grammar are so very different. They place value on different sentence constructs, orderings, and word types that make the sentence (and whole piece) just different between the two languages (of course translators do their best, but an English version of the Metamorphosis does not compare to a German version). A similar comparison is between Don Quixote in Spanish and in English. You might be able to translate it to English, but there will be many differences (subtle, yet the feeling is what is important) that can change the way the book is read.

And while literature may not be the utmost important thing in the world (and perhaps world unity is more important), what the literature represents is important: the culture. That different languages place different importance on different words, grammar, syntax, etc. makes the languages not just hard to translate, but almost impossible to do so without losing part of the meaning that is only comprehensible in the original language.