I'm not sure capex is the best metric, PPP make's China's money go further. Their techsci funding (subsidizing) produces more per unit.

Also consider that Ai needs electricity. China has more than 2x the generation capacity and is building faster than anyone else. Here in the US, we are facing pushback that will slow things down.

Then there are the model capability questions. (1) Frontier models are being restricted (2) eventually models will be good enough for most tasks. This later point is why I believe the most of us will eventually have unlimited plans like our mobile data. Switching model/providers is very low effort as well. We already have tools like LiteLLM and GoModel that provide a single endpoint to this capability.