I can sit here and try to re-discover the fundamentals of physics from the ground up, or I can go to a library and read a textbook.
Discovering from first principles is the honorable path, but it is a colossal waste of time. To get to the state of the art, you have to steal knowledge. Only then can you begin to understand and improve it.
You seem to believe the Chinese have some God-given right to get to the state of the art. No, there's a reason things like intellectual property, copyright, patent, etc. exist. How people here are defending the Chinese theft of proprietary US secrets and technologies is beyond me.
The other things is that why we can have such long copyright terms, but not the same for patents, is because it didn't use to matter. There were real limits to making anything useful out of it. Patents on the other hand outright suppresses innovation in the short term to reveal the knowledge to everyone in the long term.
The third things is of course that something can't be secret and morally defended by intellectual property at the same time. At least not from a functional perspective.
Discovering from principles is not a "colossal waste of time". Ask any Physicist if they thought studying and understanding Classical Mechanics was a "colossal waste of time".