Moderation is necessary and great for a healthy online community. Abuse of moderation is a tool used by misinformation campaigns. The parent comment clarified the difference with abuse being when moderators take down legitimate, non-hostile comments because they disagree with the point being made.
I think right now we're seeing more cases of moderation abuse on various forums because the consequences are so unpredictable. YouTube videos, tweets, Facebook posts get flagged at really inconsistent rates.. there was an excellent post highlighting this a few months ago in regards to Twitter[1]. This is a mark of tyranny, where you have vague rules that are selectively enforced so your populus doesn't know the limits of what's ok and they censor themselves. In this case it's Twitter/Facebook/YouTube being the tyrants, but they're acting this way because they themselves are afraid of what laws might hit them from our unpredictable government.