Culture and nationality is not defined by race.
My host family gifted my yukata to me. My sisters wanted to teach me about summer festivals and hanabi watching. They showed me how to put it on and we did purikura together when we got dressed up. (they’d laugh if they saw my picture today with the left side under the right though, oops.) They shared this with me.
Wearing yukata or kimono is not culture appropriation. It can be offensive when you do it wrong, or wear it as a mockery (Obviously don’t do that). But in my experience in Japan, people wanted me to take part and learn and appreciate their culture. I was dragged to a lot of stuff just because they wanted me to learn! Even a funeral, which was awkward but amazing.
My host mother often talked about how happy she was to take me to museums and show me how to participate in tea ceremonies or Ikebana. It made her proud of her own heritage, and happy that someone younger was interested when my sisters just wanted to know more about American culture from me.
Its also sort of rude to the many, many non japanese living in japan, who are a different race but have lived in japanese culture for generations. I met plenty of spanish, australian, and black japanese civilians who spoke fluent japanese, wore kimono, and participated in their country’s culture.
