The issue is that the CCP is only admitting to 2,000 known cases. The actual number of infected must be much higher, as mathematical models suggest. Furthermore, like you said, that city has a population of over 10 million people, with everyone traveling and coming home for Chinese New Year. That means more people in cramped confined places, sharing food and etc—a perfect breeding ground for the virus. It is not plausible that only 2k are infected at all considering how fast even the “reported numbers” are climbing. If it wasn’t a “big deal” then the CCP wouldn’t have multiple cities/entire provinces on lockdown. That’s insane that amount of restriction—over 20 mill quarantined. This type of reaction from the CCP indicates a far larger and more serious issue than they let on. In such a large and populated city the virus will spread swiftly if not properly addressed. So yes, this is quite a concern. China is the one of the worst places for this crisis to occur, especially concerning that right now we are amidst the largest Chinese holiday celebrations. The other concern is that we do not yet know the true mortality rate of the virus.