I don’t really believe in microaggressions when it comes to Japan. I mean, I get it, there are definitely subconscious assumptions being made about foreigners, but I don’t think they are necessarily demeaning. Often annoying, but not always demeaning. (Conscious assumptions, however, do exist, and they are often demeaning.)
The one I’m thinking of at the moment I’m not even sure qualifies as a microaggression: having someone complete a sentence for you before you can finish it.
I was in Japan for the first time in four years over New Years, and I had the distinct displeasure of exercising rusty language skills. The first night there I was telling my former roommates that I’d lost a lot of vocabulary and had a hard time unearthing it in the middle of conversation. A few moments later we were talking about the U.S. presidential election, and I broke out 世論調査 (よろんちょうさ, public opinion poll); they all started laughing at the かたいness of the word and said I was doing fine.
I never found myself in that much trouble, nothing I couldn’t explain my way to understanding/a word, but I did find myself at a loss once I returned home and was speaking Japanese with coworkers.
I caught a cold at the end of my trip (one that seems to have relapsed) and was jetlagged upon my return. After work I was on the elevator with a woman who speaks quickly and often intermixes English and Japanese in conversation. She asked if I was still sick.
I explained that I was and that it was worse because I was also trying to get over jetlag. I said something like. 時差ぼけまだ大変で、今朝５時半起きてずっとベッドの中で
This is when she cut in and said うだうだしてたの？ Which, I guessed, was exactly what I was trying to say. I just didn’t know the word in this case, so even if I had gone spelunking for it in my memory, I wouldn’t have found it.
A quick look at Japanese dictionaries (the 和英 aren’t so satisfying for this word), suggest that うだうだ has two meanings: 1) doing/saying meaninglessly stuff interminably, 2) spending time restlessly.
Being interrupted can do one of several things. It can limit the amount of unprompted/unassisted speaking practice (bad), it can dismiss whatever it is you are trying to say (neutral, depending on what it is you’re saying—who knows, maybe you’re a dumbass), or it can correct and assist in cases when you actually need the help (good). It’s up to your conversation partner to judge whether it’s appropriate to butt in, and it’s up to you to judge whether your conversation partner has been a jerk. Nothing is given.
Also, take a look at these animals performing うだうだ.
I found them from a Google Images search, and you can see more/purchase them at this site apparently.