> China lied about the virus. They banned investigators from outside the country and tried to cover everything up. Experts knew they'd lied previously about SARS, but rather than assuming the worst they more or less assumed it probably wouldn't be a big deal

They shared the genome quite quickly. Scientists got working on it ASAP, around the world. Chinese hospitals and medical experts were also pretty quick about sharing detailed information about what they knew of symptoms, disease progression, and their local best practices for keeping healthcare workers safe. (Sadly many hospitals around the world did not follow those...)

Independent epidemiologists, virologists, etc. in the West immediately started issuing urgent warnings, begging governments to take decisive action. Neighborhoods in Western countries with significant Chinese expat populations were paying attention and started masking up and staying in their houses by the beginning of February.

What outsiders could objectively see in January was that China shut down the entire national economy and transportation network, instituted unprecedented public quarantine/curfew measures (blocking off neighborhoods, only allowing occasional trips out of apartment buildings, stopping all inter-household gatherings, locking domestic immigrants out of their own apartments, forcing people into temporary isolation facilities, etc.), shifted massive numbers of healthcare workers to Hubei province, vacuumed up whatever PPE supply they could, started building temporary hospitals at ludicrous (probably structurally unsound) speed, etc. There were videos online of people getting welded into their own apartments or forcibly shoved into vans by the local police, falling down dead in the street, large-scale public disinfection of streets by armies of workers in hazmat suits, etc. etc. It was like a post-apocalyptic horror movie.

The provincial government clearly screwed up by wasting time and covering things up in November–January, but after the national government took over the response was swift and decisive. (I think some steps were clearly an overreach and some of the implementation was sloppy and disorganized, which ended up hurting a lot of people. But it is easy to criticize from afar, and at the time there were many unknowns.)

Sure the aggregated public statistics put out by the Chinese government of cases and deaths in the Wuhan area were obviously a massive undercount (partly because getting reliable data of a new disease that nobody understands yet and can't perfectly test for is always extremely difficult; there were also dramatic undercounts in Italy, Iran, the USA, etc. a couple months later), but anyone paying even the slightest attention could see that this was a huge serious threat coming for the world. Certainly by mid February it was abundantly clear that this would be a pandemic requiring large-scale coordinated decisive action by governments around the world.

Some governments (e.g. Taiwan, South Korea) took their own decisive action, mobilized a national response and spun up PPE, testing, isolation, quarantines, contact tracing, etc. ASAP, and saved countless lives.

Other governments (e.g. England, USA) were disorganized, avoided taking prompt action, sidelined local experts, and ended up with many avoidable deaths and economic devastation. Attempts by leaders in the latter countries to deflect blame to China can be rationalized by saying that China was not as forthcoming as they should have been, but frankly that is a cop out, with at least some racist undertone. It didn't take any brilliant insight to see that the Chinese government considered the epidemic to be a catastrophic national crisis, and that there was significant risk for a severe worldwide crisis.