As the media didn't prime their reactions to be against China nor stoking an existing concern by fearmonger and sensationalism. Toss in every major US media company and Hollywood do far more business in China than Russia. China is a huge market with an insane government. Media does not want to bite the hand that feeds.
Maybe a different comparison? How about we compare China's actions or inactions on this virus to Russia's actions and inactions concerning the Chernobyl disaster?
Remember that Russia initially denied anything happened, even though it knew otherwise, and kept denying it even though the radioactive cloud crossing Europe was obvious to those keeping track of such things. it was only later that it opened up about what happened.
For China, we had an initial denial, even internally, and then considerably more openness about the details of what they knew about this virus (although perhaps not in terms of death rates).
Again, in this case, both were unexpected events. As far as I can tell, Russia comes out slightly worse, but the overall impact of their denial was less than what would have happened if China had not let everyone know what was going on until cases showed up in other countries. So, Russia was less honest, but the stakes were higher for China.