There was this post on This Is White Privilege:
bendingdick-cucumberbatch asked: Hi sorry, just wondering about the “White privilege is going up to someone of color and trying to “speak their language”” post. I am studying Japanese right now, if I were to ask someone who I know speaks Japanese to help me with my pronunciation or if they could practice speaking it with me, would that be racist?
“Hey, you said this thing was racist, but what if I did a completely different thing? Would that be racist?”
I am in the population that’s most often guilty of the obnoxious behavior in question, but I have also lived somewhere else, where I was the exotic one, and I was among the people who had to deal with the obnoxious behavior in question. So I think I have a useful perspective on this! I will expand on the TIWP mod’s answer a bit.
On the one hand, we have the “HOLY SHIT YOU’RE A FOREIGNER!” approach, in which you see someone, who is outside of your acquaintance, who appears to be from a different cultural group. You know a few words of a language which you assume this person speaks. Maybe you have actually seen this foreign-looking person open their mouth and speak the language! Or maybe you have never heard a single word in this person’s voice, but either way, you assume they speak this language, and you know a few words in it, so you start blurting inanities at the foreign-appearing person like they’re gonna throw you a cookie as a reward for doing a trick. These inanities are usually polite unto themselves (such as “hello” or the equivalent), but the message such an interaction sends ultimately comes down to you pointing out to someone that they do not appear to be part of the native population. In the Global North, a frequently seen example is some clueless McWhiterson who sees an East Asian person on the street and shouts “Ni hao ma!”, with that being one of maybe five entire phrases the shouting person knows in Mandarin, not realizing and not even considering that the person they’re shouting at is Vietnamese-American, is a U.S. citizen who’s been here since early childhood or birth, and doesn’t know Mandarin, either.
During my time abroad, I amassed a lot of examples of people showing off their foreign language skills to let everyone else on the street know that a foreigner was out and about, but what I dealt with the most frequently were the many neighborhood children who would drop whatever they were doing and vocalize something resembling “HELLO!” at me, over and over again, every time I appeared on the street, but then scurried away when I tried to interact with them. This went on for over half of my assignment. I only had a few weeks left in the country when they finally stopped. I may still be a little bitter about this aspect of my experience. Even the most persistent of those children, however, made more sense than the old man on the sidewalk who shouted something in Italian at me (a language I have never learned) and then got all annoyed when I stopped and asked him, in his own language, what he wanted from me. What the old man had in common with the kids was that none of them were actually talking to me. The purpose of their shouting was to remind me that I was a foreigner. Just in case I might forget.
On the other hand, we have the “We’re acquainted, and I’m trying to learn a language that you know” approach, in which you know someone well enough to know their name and a little of their life, and you have in their own words that they speak a language that you are in the process of learning. You actually speak enough of this language to hold a conversation, and you are making an earnest effort at learning more, so you go to this person, ask nicely if they’ll help you with your language-learning, and wait for their answer. There’s nothing wrong with asking. If they say no, and you try to force the issue, that’s bad, and if you’ve never shown the slightest interest in conversing with this person before you decided to use them as a free language tutor, that’s obnoxious, but if you’ve learned past the basic greetings level, and you already have a rapport established, it’s okay to ask.
I can’t find the original TIWP entry about “going up to someone of color and trying to ‘speak their language'” but I’m willing to bet the person who made that submission was referring to the former behavior and not the latter.