I find this to be a rather interesting thing myself.
The Japanese logic of forcing the students without black hair to dye it black is that it would be unfair to not do so, as they would otherwise have a choice that other students would not, as they can obviously not be allowed to not dye it black.
In many other countries, one is allowed one's natural hair color, but not dye it at all.
In some others, one is allowed to only dye it into naturally occurring colors; one might argue that for Japan anything other than black veers close to this philosophy since 99% of Japan has black hair.
In yet other countries, schools are not allowed by law to prohibit students from dying their hair in whatever color they might want. — I live in such a country so naturally from my perspective the obsession with hair color seems quaint.
But one is I suppose to appreciate that in Japan at one point only street thugs would dye their hair blond so it became a certain dog whistle. It is not too dissimilar from many North-West European schools in the early 2000s banning any and all clothing of the brand Londsdale, until some courts overruled that, as the brand became a dog whistle for Nazis, as when carefully covered the lettering leads “NDSA” which is one letter short of “NDSAP”.
The Japanese logic of forcing the students without black hair to dye it black is that it would be unfair to not do so, as they would otherwise have a choice that other students would not, as they can obviously not be allowed to not dye it black.
In many other countries, one is allowed one's natural hair color, but not dye it at all.
In some others, one is allowed to only dye it into naturally occurring colors; one might argue that for Japan anything other than black veers close to this philosophy since 99% of Japan has black hair.
In yet other countries, schools are not allowed by law to prohibit students from dying their hair in whatever color they might want. — I live in such a country so naturally from my perspective the obsession with hair color seems quaint.
But one is I suppose to appreciate that in Japan at one point only street thugs would dye their hair blond so it became a certain dog whistle. It is not too dissimilar from many North-West European schools in the early 2000s banning any and all clothing of the brand Londsdale, until some courts overruled that, as the brand became a dog whistle for Nazis, as when carefully covered the lettering leads “NDSA” which is one letter short of “NDSAP”.