"SJ can't own all female AI voices" is attacking a straw man version of the complaint, which is much narrower. The question is whether OpenAI deliberately fostered the impression of an association between their product and her performance, which she had so far refused.

To your point, there have many female assistant voices on the market, including Sky -- but what might have tripped the line of impersonation was the context this particular one was presented and marketed. I don't know where exactly that line should be, but you can certainly reject this kind of marketing without stifling anybody's legitimate career.