China's success is weird. Almost none of what they're doing should work. For example, according to their totally-not-propaganda publication describing how they controlled coronavirus, the foundation is public temperature screening - it's that which feeds potential cases into testing and later contact tracing - and that just fundamentally doesn't work. The false positive and negative rates are atrocious, especially if you do it with forehead thermometers and thermal cameras like they do. They also do big, high-profile testings of entire cities which don't seem to find anything, making them useless. Meanwhile, there kept on being incidents like someone admitted to hospital with coronavirus symptoms in the main city of the region where the big outbreak was known to be at the time not getting tested for coronavirus and spreading it in the hospital. Or China completely missing an outbreak until it happened to spread to the better-tested and better-protected Beijing.

There are some things they do that should have some effect, like treating everyone from Wuhan like a plague carrier very early on in the outbreak (bit late to replicate that now, and China and the WHO loudly campaigned to make sure other countries didn't anyway) and quarantine for people returning to the country. We know from New Zealand though that even dedicated quarantine hotels are too leaky to really work at China scale - and there's also the problem of their extremely long land borders.