You really think China doesn't have massive amounts of capital expenditure related to AI? They're actively bootstrapping an entire chip industry.... https://www.reuters.com/world/china/china-prepares-295-billi...
China’s chip industry is 7-10 years behind, and that is because they are desperate and have been throwing money at it. But technological progress requires more than just money.
Relatives vs absolutes. America will spend $500B and because of leaky pipes that's effectively 100B going directly to what's needed. China gets a lot of bang for their buck so even if they're spending a fraction of the US, they make it worth their money.