For this movie universe! Because all the cybertronians won't be speaking English, since they haven't leant it yet (through internet). It will just be gibberish with subtitles. Unless they do a Disney (with their animals) when cybertronians do speak "English" but when theyre in a different prospective, they are actually speaking cybertronian. Get what I mean? Plus, all the cybertronians look the same... Unless they make it out that they scanned something to become protoform?