There's only so much good sanitation processes could even achieve here, in the same way there's only so much that bad sanitation processes at a restaurant can do. Bad sanitation in a restaurant almost always means an increase in known pathogens that we can either take care of fairly easily, or even in the worst case scenarios of something such as botulism, have limited ability to spread among the general population.
The risk of an unsanitized kitchen is just totally different from that of even a somewhat sanitized wet market.
We - including China - do not have a good understanding of the potential zoonotic diseases from the large variety of wild game that is captured and sold in these markets.