On May 13, it was discovered that YouTube would automatically delete certain phrases that are critical of the CCP (Chinese Communist Party). The Epoch Times explains which phrases with some background:
One apparently banned phrase is “gongfei” (共匪), which can be translated as “communist bandit.” It seems to date back to the Chinese civil war era.
Another phrase that has been deleted is “wumao” (五毛), which literally means “fifty cents” and is commonly used to describe the army of internet trolls the CCP uses to spread its propaganda online. It’s rumored the trolls used to be paid around 50 cents per post.
Repeated tests using both phrases, even somewhat more positively instead of critically, all showed the comments being deleted in under 20 seconds at most, strongly suggesting an algorithm at work and not human review.
It wasn’t until May 26 that the situation got enough media attention to pressure YouTube to “look into it.” Later in the day, YouTube issued a statement with the results of the investigation:
UPDATE: Just confirmed that this was an error in our enforcement systems. It didn’t take proper context into account and incorrectly removed some comments. We’re working to fix it as quickly as possible.
– YouTubeInsider (@YouTubeInsider) 26 May 2020
So it was all just an accident: censoring for the CCP even though the platform isn’t officially available in China.