I think they do it to make sure people get the point that the person mixed.
I dunno, you'd be surprised how clueless many people from Asia are about well....genetics. Because I've been to Asia, including Japan, can speak several languages to a certain degree, and have interacted with them, so you would be surprised what they don't know. Which makes sense, since they would know more about their respective country. But this lie has to stop lol.
I have never been i Japan but I kind of expecting that a highly educated country like Japan know basic info how genetics works.
Like i m turkish and despite being blond is a thing in turkey i have never meet a complretly blond guy and met way more people with a "stereotypical asian"apparence cause the east asian genes that many people actually have are strong af so it just sound so fucking stupid for a 1/6 japaness person to legit have blond hair just like that
Ok do japanese people not know that having blonde hair is a recessive gene? If you're mixed with half caucasian genes it's highly unlikely you'll have blonde hair or blue eyes, unless the japanese lineage somehow had something else there. JUST SAYING. -_-. I see so many mixed half caucasian and half asian characters in Japanese comics with Blonde Hair or Blue eyes, but dude, that rarely happens.