Some people still do believe them for what they have to say on this, for whatever reason. When you’ve got your quasi-ally (Russia) closing the 2000 km land border you know something is not right (especially as Russia is not known for caring that much for its citizens), but maybe the WHO officials know better from half a world away. On top of that the actual videos that come out of Wuhan are really heart-breaking.
The point is that China implements severe travel bans within their own country, and yet are reprimanding another country for trying to do something similar.
China also claims to have it under control (in the same reprimand) yet Coronavirus has snuck through their borders numerous times and is now in a dozen countries.