@Alex
A very rough summary:
Taka: Language reflects the culture, so when Japanese speak in Japanese they follow the concepts of Honne and Tatemae (not displaying their true feelings in public) but when they speak in English they are more straightforward.
Aki also speaks more straightforward in English but wonders if this is just due to limited language skills.
Daichi: Japanese are polite and shy but this image is also a burden. The image of the Japanese soccer team that cleaned their locker room during the World Cup is known everywhere and now everyone expects the Japanese to behave accordingly.
Ok, this is really only a rough summary of the main points. Not a translation.
I do have the feeling that the Japanese are politer and more reserved in public as the Germans for instance. Yes, Germans can also hide their real opinion if they have an agenda or don't want to hurt someone's feelings but in general they like to voice it openly. Many people regard me as rude, while I find myself straightforward. In Japanese, many things are expressed very indirectly. Well, I don't think one way or another is better. There are just different codes of communication in different countries. Of course, personalities differ as well, so there are extrovert, straightforward Japanese and introvert, reserved Germans as well but in general we follow the codes of our culture in order to be heard and accepted. When we talk to someone from another culture who follows different codes, we try to find some common ground and create a third space where we don't entirely follow our own codes but adjust a little to the other one.
I agree with Taka-san. Even the Japanese language itself has different levels of politeness, which other languages don't have.
You said that people in other countries do not express their opinion in a straightforward manner either. That, however, I disagree with. Russians are very straightforward, rude, even. I have heard some things from my colleagues and my boss which I don't think I would ever hear from a Japanese person. I also constantly meet rude Russians/Ukrainians in real life and on the internet, even here on italki, while I've never met a rude Japanese person. Also, many of my language partners (from China, Canada, the U.S...) ask me to teach them some vulgar Russian (swearing), but none of the Japanese people I've ever exchanged with asked me that. So in my experience, Japanese people are indeed politer than many other cultures.
言語は文化を色濃く反映しているし、パーソナリティも言語から影響をうけて作られるから、その言語と話す国、相手によって多かれ少なかれ誰も同じように対応すると感じる。
程度はやっぱり、日本人に日本語で話す時の方が強くでるなぁ。
@ Hanji
You said you are more straightforward with foreigners because otherwise you could not convey what you want to say. True. When translating from Korean to German I have to change at times the content in order not to cause confusion. In a business letter someone applied for a job. He wrote: Although I might not be qualified to do this job... It is of course only an expression, Koreans do not want to boast and always present themselves as humble.
Another example: When one is invited and compliments that the food is nicely prepared, the cook usually says: It only looks good, unfortunately it does not taste.