When an organization discovers problematic content on one of its social media sites, there are three possible responses. those responses are

The three possible responses are: leave it, respond to it, delete it

All the decisions would be based on term of services that the organization give for the users.
If the 'problematic' content is still within the scope of the term of services, they would most likely leave it, if it need some adjustments, they would respond it, but if it clearly violate the terms, they technically have the right to delete it.