A lot of legit anti-Putin comments end up being marked as spam. These comments are polite and well thought out. When I try to unflag them, there is "Error undoing flag as inappropriate. Please try again."
The whole process is stupid. I could mark anyone's comments as spam and the only way you would know is if someone else replied so you can see it under the red bell. I could prevent comments from being posted altogether on anyone's channel by doing this because, the way YouTube sets this up, it only takes one person to hide a comment. So, without you getting a red bell, you won't know about it. I've pointed this out in the past, but I don't think anyone's listening. YouTube, wake up!