China should be able to replace all Japanese chemicals, even more easily than Korea could. The difference is how economical for the koreans to do it by itself.Then that's kind of like saying Apple is nothing without Korean display technologies and Tesla and Apple are nothing without Chinese battery technologies?
You said here that TSMC and Samsung are nothing without Japanese chemicals for fab processes... well exactly how much are they nothing?? Is it 2 weeks worth of supply chain reshuffling or 2 years of research and development to replace those Japanese chemicals? Or 2 hours and 2 days? This is quite an important detail before we make big claims like TSMC is nothing without xyz and Samsung is nothing without abc. Apple and some Japanese makers are also nothing without TSMC. Isn't that also accurate and fair to say? If TSMC is just a place where Japanese chemicals are used with American equipment, how come TSMC has been and is the leading foundry with no peers at the moment and the closest being Samsung? For example if there is 100 parts to this process, TSMC has the magic formula for 50 of it while various non Taiwanese suppliers have the remaining. American equipment is nothing without Taiwanese foundry tech. Japanese chemicals are also nothing without Samsung's tech.
Point is aren't Japanese tech industries often also somewhat to extremely reliant on foreign supply chains and the same goes with American ones. Chinese is arguably the most independent EXCEPT for foundries and even with foundries the Chinese can do everything themselves in-house now apart from anything that requires ASML's EUVL but can Dutch ASML produce even a 128nm logic chip? Nope but Chinese foundries can... many of them down to 28nm and they've been doing 14nm now. Is it sensible to say ASML is nothing without foundries using their equipment? The question is exactly how dependent they are and how significant the obstacle to replace supplier if required. I would imagine that Korea would get along handsomely well if Japanese chemical supply was instantly stopped. It would probably take the Koreans a few weeks or months to replace those Japanese suppliers. Who knows but I'm not the one saying they're nothing without Japan.