I'm an intellectual-property lawyer; I'm well aware of what "cultural appropriation" supposedly is — and what it isn't.
(That's why I put the term in quotes. In part, it's to tweak the noses of people who rail against something that the law doesn't recognize as "a thing." What those folks call "cultural appropriation," the law calls "laudably propagating good ideas and practices, subject to any applicable restrictions that have been duly enacted into law.")
Apparently not, since you think that "plural pronouns" are a cultural element that can be appropriated, which isn't the case when aforementioned pronoun has centuries-old singular usage -- notwithstanding the significantly greater usage and acceptance in modern times -- with the extreme minority being the bigots who attempt to deny both grammatical and historical fact, and language evolution -- because of their own bigoted, hateful views.
Being an IP lawyer won't win you any points, especially when you're ignorantly refusing basic facts of language even with empirical evidence.
(That's why I put the term in quotes. In part, it's to tweak the noses of people who rail against something that the law doesn't recognize as "a thing." What those folks call "cultural appropriation," the law calls "laudably propagating good ideas and practices, subject to any applicable restrictions that have been duly enacted into law.")