Furthermore YouTube comment are full of spam and YouTube doesn't delete them, so why is it that if they contain certain Chinese keywords (in Chinese) they do delete them?
I think this just shows their spam filtering is not perfect. They delete lots of spam, in both English and Chinese, but some slip through.
Your comment seems to imply that the ONLY comments that are being deleted are the ones with the Chinese keywords. That is certainly not true. It tries to delete all spam, but the spam detection has both false negatives and false positives. That doesn't necessarily mean there is a conspiracy (doesn't mean there isn't, but provides no evidence that there is)
Excuse my bluntness here, but that is a very lazy excuse. A lot of comments are repeated, utter trash that span multiple channels and videos from known bad actors. Sure no spam filtering is perfect but in this case it's obvious YT has gone out of their way to handle that data differently.
It’s the other way around: an expressed hateful opinion may be considered hate speech by the law or someone. And an opinion may be considered hateful. But the other way doesn’t make any sense.
"All <n-word>s need to go back to Africa." (clearly and overly hateful)
"All black people need to go back to Africa." (still hateful)
"All African-Americans need to go back to Africa." (All words are accepted, but the notion is still rather hateful)
No matter what words one uses it could be considered hate speech by today's definition. Disclaimer: I do not nor do I advocate using racial slurs, the stub in here was just to prove a point.
In the case of communist bandits, it's a criticism of a political ideology, and in particular here one party. Criticism of political parties and ideologies is completely fine, even when expressing insults to them. Expressing threats of violence or other crimes isn't permitted or moral, but expressing dislike or disrespect is perfectly valid. Can anyone say they've never expressed disrespect to any ideology or political party in their life?
Does that offend you?
Would you be as happy to see fascism protected from negative commentary online, as you clearly would communism?
It's like censoring someone commenting "It's FBI sponsored" or "Russian propaganda". Sometimes a view words in a context can say as much as a long sentence.
Also in Chinese thinks are a bit more complicated due to how different glyph can be combined and/or used in conjuncture. So I wouldn't be surprised if there is a situation where commenting with a single Chinese glyph is saying as much as a long sentence!
Chinese characters aren't magic. Putting two characters next to each other isn't fundamentally different from putting "Russian" and "propaganda" next to each other. You could write a sentence with just a single-character word, but that's not going to be more expressive than a single word in any other language.