Sadly we can’t be surprised when the NSW premier herself blatantly ignored that health advice (to isolate until receiving a negative test result).
Don’t listen to conspiracy nonsense; China, like so many dictatorships in history, has been secretive to try and minimise their embarrassment at the virus appearing in Wuhan and to hide whatever mistakes they made, but to say the virus wouldn’t exist is ridiculous.
As @turdall said the response to the pandemic is what really matters, and although mistakes will inevitably happen from time to time, learning from what happens and following health advice is what’s needed instead of ignoring it (and pretending the virus will magically disappear).