What does cultural relativism imply about the moral status of social reformers?

Cultural relativism also has the peculiar consequence that social reforms of every sort would always be wrong. 
But in real life, it actually told otherwise. For example, take a look at the French Revolution, when the Government was so corrupted to the point where people became fed up and decided to overrule them. In this case, we can't really say that the social reform is in the wrong side.