What they were actually trying to combat was China preventing the US from continuing to radicalize and use the Uyghurs as a front for regime change operations.
The U.S. State Department’s Office of the Legal Advisor concluded earlier this year that China’s mass imprisonment and forced labor of ethnic Uighurs in Xinjiang amounts to crimes against humanity—but there was insufficient evidence to prove genocide
I believe that "technically, we cannot prove it's genocide, just crimes against humanity" is still a pretty clear and bold statement.
They’re putting their spin on it. In reality, the State Dept has been trying to radicalize and train the Uyghurs as an extremist front to destabilize the region. China has been working to detain, de-radicalize, and rehabilitate the extremists.
Even in their own spin, the State Dept does not imply any loss of life or mass casualties.