> Can an honest argument be made that the United States and China (let alone some of the other countries on the list) are even in the same league?
No one is in the same league as China with regard to the death penalty (so the "let alone" is backwards, there), but leaving aside China and handful of Middle Eastern countries the United States is far out in the "heavy use" of the death penalty compared to every other country on Earth.
So you probably don't want to bring up the "in some countries, criminals might get killed instead of imprisoned" in a discussion of how the US is worse on imprisonment than every other country on Earth, because, compared to all but a handful of the ~200 countries on the planet, adding in consideration of the death penalty on top of incarceration exacerbates rather than mitigates the ways in which the US is worse.