I wanted to ask exactly that question. Thank you French fan! And thank you for letting me know about it, matsumoto.
As for Western folks and Eastern folks, I don't know much about Japanese entertainment industry because X Japan is the first and the only band I'm into(I'm learning Jrock and Jpop little by little though). But as a Korean, I'm very familiar with Korean entertainment industry. I agree with returner. If a kpop member wears Hakenkreuz, they would be harshly criticized. We learn about Nazism not only at school but also through books, movies and other media("The Diary of Anne Frank" is a must-read book. "La vita è bella" and "Schindler's List" are super famous).
However, the level of criticism due to wearing Hakenkreuz is nothing compared to the one they will receive when they wear "Rising Sun Flag". When a member of SNSD posted a Rising Sun Flag emoji on her snapchat, she was almost trampled by angry netizens. We have our own historical issues and respond right away to the stuffs directly related to our history. I mean, we understand the meaning of Nazi symbol over the head, but cannot feel it from the heart unlike the symbols that are related to our history directly.
Nevertheless, the Nazi symbol is a kind of taboo in our society as well.
Back to religion topic, last year, cheap comedy tv series were broadcast in Korea. The synopsis is that a man went to the Middle East and became a wealthy Count, and one day he happen to know that he had a daughter... such a story. The drama didn't get any attention until one day they announced the official apology. It's because they received tremendous protests from Muslims for the reason they made a joke about Islamic culture. They apologized in English and Arabic and deleted the footage from the VOD services, but anger of Muslims lasted long. Some people even went to the station and threatened that they could be terrorized if they do this again.
It was a shock to me. And I first learned the word "cultural appropriation". There is no Korean word for "cultural appropriation". We lack education and awareness about such things mainly because our society is not multicultural. I searched for English posts on "cultural appropriation" and found that many kpop idols were being blamed for dreadlocks, and the use of some Indian or Arabic images in their music videos. At first, it was very difficult for me to understand. But now, I'm kind of educated in some way.
We can say crucifix is a symbol of Catholic or Orthodox, right? But no one blames Yoshiki for using the necklaces as a fashion item. What if he used the symbol of Islam as an accessory? It's hard to imagine.
I still can't understand it. "cultural appropriation" does not apply to Christianity?
I'm not blaming Yoshiki. I just can't understand the meaning of "cultural appropriation" perfectly.
+ I have a photo of Sugizo wearing a Nazi armband(holding a whip). But I am sure that Sugizo is very far from Nazism. Some people even call him "the left" because of his actions or remarks. Yes, Japanese rockstars do not seem to read much into the Western symbols.