The world is dependent on trade with China, far more than Russia, you're just ill-informed.
No, it is not. In reality, there is not much that comes out of China that is critical. And a great deal that is made comes through middlemen in Taiwan. Like Foxcon, the largest electronics manufacturer in China, which is Taiwan owned. DO you really think it will continue operations as usual, with their home nation under attack? No, you are living in a fantasy if you think that.
In fact, look once again to Russia. They thought that Europe was dependent upon them for natural gas, and if they cut Russia off there would be blackouts and people would freeze. Hence Russia attacking in the Winter, not the normal time to start an offensive. But even with the NG cut off, they are adapting. There is nothing coming out of China that the world can not do without. And as I said, the nations that China took that business from would quickly take back a lot of that work again. So what, China cuts off the inexpensive COSCO products, do you think that strollers, desks, and cheap particle board furniture is critical to the world?
And as I said, they do not even "make" the products! Tell me, exactly how much of these products are actually designed and created in China? The answer is easy, none. They are made elsewhere, China is simply where they are reproduced. They are not an "originator" nation, nothing of importance actually comes from a Chinese company. Apple, TI, Intel, Motorola, the list goes on and on. Made in China, designed and engineered in other countries, by other companies.
Tell me, what is the best selling Chinese cell phone outside of China? Video game console? Television? Airplane? Car? Computer? Camera? Medicine? Medical equipment? Anything?
Simple fact is, China is a giant "Xerox nation", getting rich by providing cheap labor by making things crated by others. Almost nothing they make they actually own! They make it for others countries and companies.
To your second point, I'd like to see sources that explain how the Chinese navy as a whole is somehow incompetent in every aspect.
I never said that, but it is in the areas that matter most.
When talking about Naval forces, they are mostly described as either "Blue Water", or "Green Water". A true "Blue Water Navy" can operate for many months at sea, being provisioned and supplied entirely at sea. All food, fuel, repair parts, personnel, and everything else supplied by the home nation via air or sea supply ships. And the nations best at it are the US and UK. Because both nations have relied on that capability for over a century.
France is also pretty good at it, but not many more bother anymore.
China is more like India and Brazil, but even less so. Because at least India and Brazil are known to send their fleets out for months at a time, even if they do remain somewhat close to home. China on the other hand has severe and obvious gaps in how they are using their navy.
First of all, it almost never leaves port! And when it does, it goes out as a bunch of ships, does some exercises for a few weeks, then returns to port. They do not really conduct "fleet operations", just a bunch of ships that go out and return together. Which is why their UNREP is so pitiful. They have never needed this capability, never practiced it, and are trying to act like simply having a few UNREP ships now makes them capable of doing UNREP. That is like simply giving a kid an AK47 and calling him a "Soldier".
Their sea handling, gunnery, and many other things may be excellent. But unless they start to operate as a true navy, they will never be more than a glorified Coast Guard. That is not derogatory, it is simply the role they do. And have shown absolutely zero interest in trying to change that. Of course, since the PLAN comes in a distant third after the PLA and PLAAF, that is not surprising. China has never been a naval power of note, and it likely never will be. They have no real "naval tradition", and think that buying some fancy toys is all they need.
