The accused artist is Javi_Draws. I never followed her works but she seems to be a very talented environment artist (is teaching her own online class and apparently has an agent).
From what I could gleam (and what I could get from vague mentions because twitter users don’t know how to archive shit) Javi_Draws said some anti-black things and supposedly is anti-BLM...but I think she meant to say that BLM wasn’t an international organization, not that black oppression is an American only problem—but this was the beginning of last summer when the protests were firing up.
Her tweets about BLM were only brought up because she said that she found the Y2K fashion aesthetic ugly and bunch of people went “oh so you hate black fashion????? You hate black people????? Black people invented Y2K fashion so if you hate the fashion you must hate black people!!!!”
It’s dumb
Miku is instantly recognizable and a (relatively) inoffensive design for normies to get into. There is also the fact that there is no lore established or personality of such for the vocaloids so people can more easily project onto her and her friends.