Memes

The UN hasn't explicitly called it genocide, but if you assume China's motivation is to reduce their population, it seems hard to argue its actions wouldn't qualify. Widespread arbitrary imprisonment and certainly forced sterilization would meet at least condition 4 of their requirement. The Genocide Convention's definition is below, emphasis mine:

In the present Convention, genocide means any of the following acts committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group, as such:

1. Killing members of the group;
2. Causing serious bodily or mental harm to members of the group;
3. Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part;

4. Imposing measures intended to prevent births within the group;

5. Forcibly transferring children of the group to another group.

You could argue they don't actually intend to reduce the Uyghur population, but it's hard to accept that a surge in the Xinjiang region's sterilization rate and the birth rate being cut in half over the course of three years are just anti-terrorism measures.