Yeah, the pivotal point was Russia getting kicked out of SWIFT. That forced a creation of an alternate financial system out of necessity, and over past three years it's expanded significantly within BRICS. The reality is that you don't need to have a reserve currency, you can just do direct currency swaps. But more importantly, China is basically the world's factory, and has a massive trade surplus with the rest of the world. Which means holding yuan is useful for other countries, since they can always exchange it for something tangible they need.