I would felt that words like ABC is such an offensive term. Like, WTF how do you know I’m not Kazakh, Mongolian or indegenious?? lol Had this one stranger approached me straight up in Toronto subway speaking Cantonese, after realizing I had no idea what he is talking about then he switched to Mandarin. I actually speak some Mandarin, but instead I asked him “ what do you want??” In Russian lol