And once they've been exterminated? Time to find a new race to destroy. Divide people with more and more subtle differences until the only ones left finally realize that it will never stop.
Tbf, China mostly decides who to genocide based on whether the group could provide a culture or community the government can't control. It's why they're cracking down on queers, and why they genocided the Uyghurs. Uyghurs were becoming less nationalistic for China, while LGBTQ+ identities are associated with westerners, despite the fact that we exist everywhere. Furthermore, queer theories and cultural interpretations focus on liberation from normativity and its use as a system of power. The Party does not want people to question norms or critically think about systems of power if they can avoid it. As hardliners gained power, the Party tightens their grip on culture.