Yes, but I'd bet that the connotations of "hafu" in a society where mixed race is the norm are very different from those where it is unusual.
So much so that you might consider it to be a different word, even if it happens to be spelled the same.
the reason it is notable is because it is notable almost anywhere on earth.
just off the top of my head, i can name: hawaii, the caribbean, brazil, parts of europe (italy comes to mind), east asia (especially places with large overseas diaspora like china and taiwan) all have identical cultural concepts, especially those with large populations living in america.
And in Tokyo Dialect, the 'フ' ('fu') in 'ハーフ' ('haafu') has its 'u' muted to silent or near-silent so the pronunciation is nearly identical to English 'half'.
It's practically an identical borrowing in both meaning and pronunciation; the 'u' is an historical artifact of an obsolete romanization system. Even the glyphs 'フ' and 'ハ' are used -- among other things -- to signify that a word is maintaining its foreign nature and not made Japanese.
Humanity may well end up there, given the easy transportation beginning only in the last century. Halfs beget quarters, then 1/(2^n) for ever increasing n.
uh, what? how about "half", the exact word that 'hafu' is supposed to emulate? you can't borrow a word from another language, and then claim it's unique to yours!
i'm fairly confident nearly everyone on earth knows what it means to be 'half', or just mixed race/ethnicity in general. in fact there are even places on earth where mixed race is the norm. try going to brazil. FUN FACT: the largest japanese population outside of japan is there. i think they might have a concept of hafu there. just maybe.
if you're paying attention, i think the above statement tells us more about japanese culture than the entire article, on many levels.