Okay so, my worst pet peeve is not with people whose first language is not English. My problem is with the people whose ONLY language is English, but they still don't know to speak it! Worse if they don't know how to write properly.
English speakers are actually by far the nicest as to how they treat people who are learning English. other languages... ehhh they people are a bit mean lol. English speakers are really nice.
You know what really surprised me though? Someone speaking in broken English about how they were annoyed at Mexicans speaking Spanish at them and saying they need to learn English
As someone who is constantly in learning mode, it fucks me up.