Honestly, I've noticed with a lot of things people get offended by when used outside of its context is a very Western thing. If, for instance, you were to say you were a Roman Catholic who worships land spirits a whole lot of people would get heated and say you couldn't do that... While mixing of religious traditions, even contradictory ones are done in parts of Asia and nobody bats an eye at...
I don't see white people getting mad about the blonde thing, because its so common for someone to dye or wear a wig or get blonde extensions among white, black, hispanic, Asian people that nobody would bat an eye at it. The only time I see non-white people getting backlash for bleaching their hair blonde or wearing hair pieces that are blonde, it is usually by non-white people who make assumptions about their intentions for dying their hair.
Its sort of like how I don't care if Koreans get blonde hair, as I didn't care when Tiny Harris went to Africa and changed her eye color permanently to blue. Even though it sort of looks weird..
But I might see it differently if I were Somi or someone living in Korea who was treated as an outsider for being of mixed race lineage..
Similarly, I could see a gay male living in Korea being annoyed at idols being featured in fashion campaigns, because of the way SK treats gays. I, myself, wouldn't be liked that [even though I am gay] and don't really care when CL or Lisa is/are involved in fashion campaigns, but... if a bigoted idol (i.e. Siwon from Suju) all of a sudden started working with brands such as Versace, D&G, Armani (all of which were founded by individuals who were LGBT) then I might have a problem.