After decades of actual operations of modern carriers by USN, it becomes pretty obvious that nuclear powered carriers are having poorer battle readiness and higher maintenance costs compared to ones with conventional power, despite their unlimited sailing distances.
Remember nuclear powered carriers are not necessarily having greater power outputs than conventional ones. Looking at historical data, USN operated Nimitz-class aircraft carriers with only propulsion power output 260,000 shp (194 MW) while Kitty Hawk has 280,000 shp (210 MW).
However, by the moment, USN can only rely on nuclear powered carriers as America's national goal is maintaining their global hegemony and a single carrier task group can already crush air defense of a small country at ease. Nonetheless this kind of strategy in my opinion might not work well for today's competition with China in Pacific and Indian Oceans.
- PLAN does need carriers. Otherwise they wouldn't be able to create encirclement around Taiwan with strong physical deployment which can only be challenged by USN. What it means is, PLAN will use carriers to hold some positions in the sea. Then US can only intervene by also sending their carriers for a confrontation. Therefore China can use such a stand-off to check if the US would like to have some miscalculation. DDGs will not work well in this situation as you will need fighter jets to expel US warplanes in real time during the stand-off. China's wartime goal is create a formidable no-fly-zone over the Taiwan island together with support from land based aircrafts and rocket forces, as shown in the recent carrier Liaoning's drill.
- PLAN does not rely on carriers to sink US carriers. So all the fighter jets on their carriers carriers can be dedicated for air defense when in great sea battles, which makes them vastly different to the US carriers.