The system works as it is. Each website does its best to moderate content without harming the business. From a business perspective, it'd be ideal to never mode

The system works as it is. Each website does its best to moderate content without harming the business. From a business perspective, it'd be ideal to never moderate content, because more viral content means more money, but advertisers, governments, and users have a problem with some content, so the websites have to take a more nuanced approach to balancing the desires of these groups. At the end of the day, there is no perfect solution, but that's ok, the web is a federated network of websites and each node can set their own priorities with respect to the interests they determine make the most sense for them, leaving the users and advertisers the freedom to use as few or as many websites as suit their own prerogatives.