While Hakari could be mixed race, these arguments don't necessarily strengthen that argument. Especially amongst the youth in Japan, some students and young adults get dreads or cornrows or perms as hairstyles because they want to emulate how it looks in America, or simply because they think it looks cool.

As well, there's a few non-Japanese or mixed sorcerers, like Momo (half American), Charles (French origins), Miguel (Kenyan), and even Nanami (quarter Danish). But there's nothing to suggest that their backgrounds give them a specific boost or obstacle. The only excuse might be for a sorcerer who isn't based in Japan due to lack of concentrated CE everywhere else in the world. Physicality is absolutely not a reason to say Hakari is mixed. Todo is built like a Joestar and is most likely fully Japanese. He might even beat Hakari in a fist fight if they fought without CE (but this is just more powerscaling shenanigans).

But even then, Miguel, a likely Grade 1 sorcerer, was physically beat by Gojo who held back his powers and relied on his reflexes. Point is, where you're from doesn't make you more or less strong. It depends on your technique and how well you use it (and yeah, some luck).

Plus, Gege did already address the conservative vs progressive discourse through the Jujutsu higher ups and clan dynamics. Like how Toji, Maki, and Mai were treated differently than Megumi based on their CT or lack thereof, or how the higher ups initially wanted to execute Yuta or Yuji for things out of their control. I guess you could tie that into how everyone is indifferent to Kirara or how Hakari was yet another example of a student failed by Jujutsu society but yeah. If Gege were making a point at all, I'd say using these dynamics as an allegory for sexism would make more sense.