Why do people believe conspiracy theories?
This question brings out the autism. People disagree with you because you're wrong. That's why.
Facebook has been having trouble with their content moderators. Apparently it is very popular for content moderators to start doubting the Holocaust after being exposed to the posts they are supposed to be censoring. Many of them are now being fired for this, through Facebook's contractor called "Cognizant". Facebook can't find good minions to reliably do their dirty work, long term. That's pretty funny.
The entire opperation is a total financial loss for Facebook. They don't make any money by having less content. They're wasting every cent they spend but that's not the point. Conspiracy theories are convincing in proportion to how hard you censor them. That's why all these giant corporations are scrambling to do it. They have to control everything you are exposed to or it doesn't work.