Tbh because there’s no good reason not to.
All the blood status in the hp universe is a metaphor for racism but you know what’s boring? Metaphors for racism that only involve white people. Harry is often described as “dark” and like if James Potter’s family was desi and Lily Evans’s was white, that would enhance Harry’s feelings of otherness while growing up with the Dursleys because lbr Vernon was probs a flaming racist.
“Potter” could easily be an anglicized version of a south Asian last name like Potdar or Potluri, and you could make an argument for a pure blood family like the Potters engaging in and profiting from cultural exchange through the British colonization of India so there was an opportunity to establish generational wealth there.
Also on the night he died, James was making pretty-colored lights for Harry. That was October 31st. In 1981, Diwali, the Hindu Festival of Lights, started on October 27th. It lasts five days.
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