So blame youtube commentators for this post. On the face of it, its a relatively straightforward and logical question with a quick and simple answer; its a tvshow/movie/entertainment.
But if you give that answer, it just winds the person up even more and you generally get a diatribe about how 'Hollywood' treats us like idiots and they should make more effort into making things more realistic. "Make up a language/noises and add subtitles!"
I just love how this argument completely ignores the rest of Planet Earth's languages. Do other sites with a different primary languages get similar posts? "Why are all these xanaxians speaking mandarin?" etc, etc. It also kinda ignores its logical conclusion: that any show involving aliens would have to show them learning a language or five.
This isn't the worse thing in the world and its been done well before. The 13th Warrior springs to mind where Banderas picks up the nordic language just by listening for most of their LotR-ish journey.
Its would be okay the first one or two times but could you imagine it in every genre show?
Which is why they invented the McGuffins like universal translator badges/implants (Yes, Starlord has one; it says so on that bio-display in the trailer!)
Frankly, i don't need little nods or touches like that and for the life of me, I cant see why anyone else does either unless the language issues are central to the plot in some way.
Why waste time, energy and bile worrying about it? I'm pretty sure having subtitles would get on the tits of half these complainers anyway...
...there are loads more important stuff to worry about like can a Jaeger actually stand under its own weight and why didn't the russians get an escape pod as well?
you know, important stuff!