It's not a matter of smart enough. It's a matter of experience, institutional knowledge, workers skilled in the necessary tasks. The Chinese are plenty smart, despite your strawman.

Look how they're pursuing a carrier fleet. Are they trying to build a CVN immediately? Nope, they're taking incremental steps with a secondhand refurbished conventional carrier. Iterating towards a long term goal, because they know war isn't Starcraft.

It's why when they wanted to develop a modern 4th gen fighter, they partnered with the Israelis to leverage the Lavi designs that became the J10.

You can be snide and set up strawmen, or you can back up your statements with facts, not ill-informed opinions.