America is not a small population country and is still per capital emitting more than China; while China is now on a downturn (admittedly from a very high absolute level of emissions)
IMO, that remains to be seen. China is still adding new coal capacity roughly equal to America's entire coal capacity, or about ~160+GW, just in 2025(74GW)/2026(90+GW expected) while retiring almost none.
Capacity is less relevant than usage. It's not like you drive a combustion car by putting your foot to the floor on the accelerator and only modulate your speed with the clutch and breaks.