LOL you still think of analyzing China's military power from your perspective as a citizen of a Non-Superpower country.
China can easily defeat the US naval surface forces already now with their Hypersonic IRBMs which can destroy any USN Aircraft Carrier easily only. They have hundreds of those Hypersonic Glide Vehicles alone, which has Global Strike capability backed by the Beidou system.
The only problem is the dozens of US submarines that can fire Tomahawks and Stealth Bombers, and even that China has Counter-Stealth Radars and countless CIWS and a very dense AD network to minimize the damage.
Chinese Industrial Capability is 1000X times Iran's, so you have no idea what China is capable of.
China doesn't want to challenge US now because it wants to be sure it can dominate and overwhelm US in all aspects of tech before they are comfortable in taking action, and they believe time is on their side as they restrict Rare Earths to USA limiting their ability to manufacture military products.